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toral fins, tipped or tinged with black. being, that prior to their seaward Thesmolts of the river were at this time emigration, they have dwelt rejoicingly descending seawards—no difference for a couple of years in “rivers of could be discovered between them and
We certainly now agree their brethren in captivity-the latter with Mr Shaw, in regarding it as sinwere known to have completed their gular (and are willing to bear our second year; and so Mr Shaw very share of blame in that fatuity), that naturally asks, “ Is it likely that those anglers should not have troubled themin the river, which so identically re- selves to enquire what became of the sembled them, were only a few weeks older generation of parrs-that is, of old ?” We answer, in the face of all the comparatively large individuals the naturalists in the known world, which may be captured late in aunot only is it unlikely, but utterly tumn and in earliest spring, but none impossible.
of which can be detected after the The small but active fish now al. departure of the so-called smolts. luded to (call it parr, pink, fingerling, “ If the two are not identical, how or what you please), is nowhere to be does it happen that the one so conmet with for the first few months of its stantly disappears simultaneously with existence, except in those streams, or the other ? Yet no one alleges that their near vicinity, in which undoubted he has ever seen parr, as such, pere salmon had deposited their spawn forming their migration towards the during the preceding winter. They They cannot do so, because may be seen in such streams by a they have been previously converted careful observer early in April, but into smolts." so young and weak, in consequence of As in the course of former corre. their recent emergence from the spondence with Mr Shaw, both our. spawning bed, as to be unable to strug- selves and others threw every legiti. gle with the current. “ They there mate obstacle in his way, so far as fore,” says Mr Shaw, alluding to a argument and explanation of the old particular instance, “ betook them- theory of the distinction of parr and selves to the gentler eddies, and fre- salmon fry were concerned, he repeatquently into the small hollows pro- ed his experiments in a variety of duced in the shingle by the hoofs of modes, and both literally and metahorses which had passed the ford.” phorically left no stone unturned They remain in these quiet places (many a Scottish stream, as we know during the spring and earlier part of to our cost, is stony enough) to assummer; but as they gain an increase certain the truth. Having already of size and strength, they begin to traced the progress of the parr, from scatter themselves all over the shal. an inch in length, through its several lower parts of the river, especially stages up to the period of migration, wherever the bottom is composed of he was himself satisfied as to the idenfine gravel. From their small size, tity of that fish with the smolt. But however, they continue comparatively as it was still maintained by his opunobserved throughout the whole of ponents (and, we believe with few the first summer, during which they exceptions, in the most friendly spirit are seldom taken by the angler. But of the love of truth, which may cerno sooner do the two-year olds disap- tainly be felt and acted on even by men pear (as smolts in spring), than these clinging fondly to the forlorn hope that small fishes, now entering upon their a parr is not a salmon), that there second year, become bolder and more might be some error in his procedure, apparent, and then constitute, and he entered upon a new series of excontinue for nearly another year to periments, of a somewhat different but constitute, the parr of anglers, and of even more decisive nature. all other observers, whether wet or On the 10th of January 1836, he dry. But their shy and shingle-seek. observed a female salmon of about ing habits during the earlier months sixteen pounds weight, in company of their existence so greatly screen with two males of about twenty.five them from observation, as to have led pounds weight, engaged in the proto the erroneous belief already dwelt cess of spawning. The two males upon, that the silvery smolts were the kept up an incessant conflict during actual produce of the very season in the entire day, for what Mr Shaw which these are first observable, and calls “ the possession of the female." were only a few weeks old--the fact These gentry seem, indeed, to be of a
ences a game
more amorous nature than is usually lifting the spawn from the stream supposed of such cold blooded crea- (some harmless people having still tures; and, in the course of their continued to assert that he might posmaneuvrings, the males frequently sibly have mistaken other ova for those drove each other almost ashore, and of salmon), he lifted the salmon themrepeatedly showed themselves on the selves, and forcing them to spawn (in very surface of the water, displaying the manner detailed in the commutheir dorsal fins, and lashing the water nications already named), he watched with their tails, from something of the vivification and final development the same victorious sensation, we pre- of the young, and found in all cases sume, as that which infi
an entire agreement in every essential cock to strut, crow, and clap his wings, particular. so soon as he has performed his morn- Thus, on the 27th of January 1837, ing exercises.' Our observer secured a quantity of spawn was impregnated in proper time a quantity of the spawn, and deposited in a small stream which which he placed among gravel in a had been made to flow into one of his small stream of pure water. On the carefully constructed ponds. The tem. 26th of February, or forty-eight days perature of the water in the streamlet after being deposited, he could per- was 40°, that of the river water 36o. ceive some appearance of animation, On the 21st of March (fifty-four days in a minute streak of blood, which after impregnation), the embryo fish traversed for a short distance the in. were visible to the naked eye. On the terior of the egg, and originating near 7th May (101 days after impregna. two small dark-coloured spots, which tion), they had burst the capsule, and turned out eventually to be the eyes of were to be found among the shingle the embryo fish. On the 8th of April, of the stream. The temperature of or ninety days after being imbedded in the water was now 43°-that of the at. the gravel, he found the fry extricated mosphere 45°. It is this brood which from the egg, which was not the case Mr Shaw has studied up to the present about a couple of days preceding. At time, that is, which he has watched this period, and for a considerable time continuously for more than the entire afterwards, their most marked and pe period requisite to elapse after their culiar feature consisted of a conical bag- exclusion from the egg until their aslike appendage, of a beautiful trans- sumption of those characters which parent red, and greatly resembling a distinguish the undoubted salmon fry; light-coloured currant, which adhered and it may, therefore, be advisable to by its base to the abdomen. This, in present our readers with a few brief fact, is the yolk, or vitelline portion of descriptive notes regarding them. the egg, which continues to adhere to Specimens taken up for examination, the young fish, and affords probably when ten days old (16th May), had its sole nourishment for several weeks still a considerable portion of the vitelafter it has escaped from the capsule. line bag attached to the abdomen.
They still continued for a considerable Specimens removed when forty-eight period beneath the gravel, and we may days old (24th June), had no percephere observethat both the time of hatch. tible bag, but the general symmetry ing, and the disappearance of the bag, of the form was as yet imperfectly de. seem to depend, in a considerable de- veloped. After the lapse, however, gree, on the temperature of particular of a couple of months (7th July), that years, each process being more speedily form was found to be materially imeffected in a mild than during an incle. proved, and "to exhibit, in miniature, ment season. In the instance in ques
much of the form and proportions of tion, a period of 140 days was required a mature fish. At the age of four to perfect the form and features of these months (7th September), the characlittle fishes, which even then measured teristic marks of the parr were clearly little more than an inch in length, and developed. Two months later, six corresponded in all respects with the months old (7th November), an accessmall parron which Mr Shaw had sion both of size and strength was ap: formerly experimented, as well as with parent; and, on comparing the pond such as existed at that moment in great specimens with the parr of the river, numbers in the natural beds of the no marked difference was perceptible." river. He has repeated these experi. The average length at this time was ments over and over again with the three inches. same result; and, not satisfied with During the ensuing winter months,
it appears from Mr Shaw's observa. woman in a crib upon an empty nest, tions, that owing to the lowness of the and which, when called by the cacktemperature, and the consequent defi- ling of the said hen, she might pick
ciency of insect food, no accession as up in a state of " calorific influence," sto size or condition is gained by these could be the egg of a condor or a juvenile inhabitants of our rivers.
lammer geyer. Thus a specimen of nine months old, All the males at the age of eighteen taken in the middle of February 1838, months, in Mr Shaw's possession in the exhibited scarcely any perceptible dif- autumn of 1838, then manifested the ference from that last alluded to. But conditions of a breeding state, by havan individual taken when it was a year ing matured the milt. The females,
old (10th May), seemed much im- however, of the same brood, although E proved in condition, and measured otherwise in equal health and condi
about 31 inches. It corresponded in tion, did not exhibit a corresponding age and dimensions with those indi. appearance in respect to the maturing viduals which exist in the river, and
of the roe.
These two circumstances are there known as “ May parr."
were previously well known to natur. After the seaward migration of the alists; but it was left to Mr Shaw's
smolts, or two-year-olds (which takes sagacious ingenuity, to make the : place early in May), there are no other former fact bear upon the point at
parr in the river-saving, of course, issue. We shall, in the mean time, the newly hatched young concealed ho proceed with our brief hisamong the shingle-except such as tory of the brood of the spring of the correspond with the specimen in ques. year 1837. We may observe that the tion, which is the pink of the river two sexes of parr, of the same age, in Hodder, alluded to by Mr Yarrell. * the river, manifested the correspond As the summer season advances they ing character of each sex, to wity_of increase in size and apparent numbers, maturity in the male-of immaturity and are then the parr, commonly so in the female--an important fact in called, of anglers, which afford a deal evidence that all these individuals were of light amusement with the rod to in truth specifically the same. the curious in small fishes, until the A specimen twenty months old, « dread realities” of winter put an end taken from the pond on the 5th of to wading, and the wicked cease from January 1839, also measured only six troubling these defenceless tribes. inches in length, and still continued
A specimen, eighteen months old to display the characteristic aspect and (taken from the pond on 14th No. attributes of the parr; but now vember 1838), measured six inches in “ A change comes o'er the spirit of our length, and had then attained to the condition in which all the ordinary About the middle of April, the cauexternal characters of the parr were dal, pectoral, and dorsal fins, began to strikingly exhibited. In point of assume a dusky margin, while at the health (and, we hope, of happiness) it same time the body of the fish exhibited was not exceeded by any of the cor- unequivocal symptoms of a silvery responding inhabitants of the natural aspect, “ as well as an increased ele- ** streams of the river. The reader will
gance of form."
Specimens two particularly bear in mind that the years old, were taken from the pond on individual specimens now alluded to, the 20th of May, and had then assumed which we know to have been examined the migratory dress. Their companby our best practical naturalists, and ions in captivity, it was quite apparent, to have been by them admitted to be had also undergone the same decided parr, usually so called, were yet, from change, and it is worthy of observa. the process employed by Mr Shaw, tion that a marked alteration in their necessarily and unavoidably the young habits also occurs at this period. of salmon. They could no more be " While in the parr state," says Mr the young of another species, than the Shaw, " they show no disposition to egg of a hen cooped up by any old congregate, but each individual occu
* “ Pinks in the river Hodder,” says Mr Yarrell, “in the month of April, are rather more than three inches long, and are considered to be the fry of that year.”-Supplement to British Fishes, p. 6. These “ pinks,” Mr Shaw has proved, are a year old by the time alluded to, while the "fry of that year” are then, in fact, only quitting the gravel for the first time,
pies a particular station in the ponds; were converted respectively into a and should any one quit his place dark-bluish black upon the dorsal with the view of occupying the posi. region, and into sil very white or tion already possessed by another, the the lower sides and abdomen. Vari intruder is at once expelled with an ous other specimens presented to the apparent degree of violence. But so Royal Society exhibit the same extrasoon as the whole brood has perfected ordinary change; and some of these the migratory dress, they immediately distinctly show, as it were, the intercongregate into a shoal, and exhibit mediate or transitionary state between an anxious desire to effect their escape the parr and smolt. They occupy in by scouring all over the ponds, leaping one respect, indeed, a most dubious and sporting, and altogether displaying position; for while they may be said a vastly increased degree of activity.” to be above parr in relation to their
It appears, then, that the great con. previous existence, they are below stitutional change which converts an smolts in the actuality of their condielderly parr into a juvenile salmon, tion, and far from the silvery splendour usually commences in the month of of a future state. Nevertheless, the April of the second ensuing season whole belonged to broods which, as after the fish is hatched; that is to already mentioned, were the original say, when it is about two years old. produce of an adult male and female The specimens marked Nos. 10 and salmon, and so could not (in spite of 11, in the collection transmitted to the whatever exertions they might endeaRoyal Society by Mr Shaw, beauti- vour to make to the contrary) be fully exemplify the change in question. Otherwise than the natural young of No. 10 is the individual already allude these fishes. Mr Shaw, then, we may ed to (although we meant nothing per- here observe, has proved two facts of sonal), as having been removed from the highest importance, alike in the the pond on the 5th of January 1839, natural and economical history of the being then twenty months old. We species in question,-Ist, That parrare may state once more that it is a parr the young of salmon—being convertible -exbibiting the form and features of into smolts ; and, 2dly, That the main that well-known fish. At this period body, if not the whole of these smolts, No. Il presented precisely the same do not proceed to the sea until the seappearance, but it was allowed to sur- cond spring after that in which they vive until the 24th of May, by which are hatched. * time it had rather more than comple. To state the matter then shortly, ted its second year. During the lapse and in a mode which we suppose
Dr of these additional four months, it Aristotle would call syllogistical, we gained only half an inch in length, think we are entitled to say, in more but it cast off the livery of the parr, especial reference to the twospecimens and assumed that of the smolt or young
last alluded to, " These are young salmon,--this signal change consisting salmon-one of these is a parr,chiefly in the following particulars. therefore the parr is the young of the The black spots upon the opercles salmon." But this announcement disappeared, the pale-coloured pectoral neither ourselves nor any body eise; fins became deeply suffused with a whether peer or peasant, could have dark or inky hue at their extremities, made without the sagacious, praise. the broad perpendicular bars worthy, and perfectly conclusive ex. blotches (from which the parrin periments of Mr Shaw. many districts takes the name of fing- This ingenious enquirer has not erling) on the sides were effaced, and only settled this disputed question to the prevailing tints of dusky brown our own satisfaction, and consequently above, and of yellowish white below, to that of the world in general, but
* We may here note, that although Mr Shaw could never perceive that any of the river fry attained the migratory state till the second spring after that in which they are first found among the shingle, he yet informs us that one or two individuals of each of his own broods assumed that condition at the age of twelve months. This circumstance, however, he is inclined to attribute to the higher temperature of the springwater ponds having hastened the ordinary natural change; and he deems himself strongly supported in this opinion by the fact, that no similar instance of an early or premature change has ever occurred among other individuals reared in correspon:ding ponds, supplied by water from a rivulet, the temperature of which thi oughout the year ranges very equally with that of the river Nith.
has moreover instituted an additional doubtedly this,--that one of these male
and very singular series of experimen- parrs, so successfully used as a parent t tal observations, in order to illustrate, (No. 12 of R. S. Ed. Collection), had
if not explain, that curious peculiarity been itself produced between another already mentioned--the sexual matu- parr and a female adult salmon; in
rity of the male parr. His frequent other words, it was what naturalists ? observance of this maturity, and of (in the very recent and possibly still
the consequent association of the parr existing days of the supposed specific e and female adult salmon, suggested distinction of the parr and smolt)
the idea of the following practical would have designated a hybrid or i experiment:
mule. Now, it is admitted by physioIn the month of January 1837, Mr logical naturalists, that the rule in reShaw took a female salmon, weighing lation to these mixed productions from | fourteen pounds, from her natural kinds not specifically the same, is-
spawning bed in the river; from that they do not breed at all. Yet 1 whence he also took a male parr, this very male parr, originally pro
weighing one and a half ounce. With duced by a parr and salmon, became the milt of the latter he fecundated itself the proud parent of a numerous the ova of the former; and placing progeny of most promising fry. Now
the spawn in the small streamlet this is a fact of great importance, bei which acts as the feeder of one of his cause it had in truth been objected to
constructed ponds, he carefully ob- Mr Shaw's earlier experiments, that, served its growth, as he had previously by a forced alliance between the parr
that of the salmon spawn impreg- and salmon, he had not proved their s nated in the ordinary way, and found identity, but had only succeeded in
both the hatching and subsequent producing a hybrid, thus, like another s growth to correspond in all points Caliban, " peopling the isle with
with the usual ongoings of nature. monsters." But the brood in question This extraordinary experiment was in no way differs from its predecessors repeated with the same results during produced under ordinary circumthe winter of 1838, and the parrs stances; and Mr Shaw has justly (taken from the river) which had observed, that, if parr were actually been used as males, were kept alive a distinct species, the result of their till spring, when they assumed the attendance on the female salmon migratory dress of young salmon, would be universal and irremediable " and no mistake." He then tried confusion among these migratory in. a corresponding experiment, by im. habitants of our rivers, “ from the pregnating the ova of three adult circumstance of the male parrs in a salmon taken from the river, with the breeding state occupying, in great inilt of three parr bred in the confine- numbers, the very centre of the salment of the ponds, and the results in mon spawning-bed ; while the female these cases were likewise the same, salmon herself is at the same instant both as to hatching and final growth,- pouring thousands of her ova into the this fact further demonstrating the very spot where they are thus geni. constitutional strength of the pond ally congregated." bred parents, and that they had not But we fear we must prelect no deteriorated, or been in any way more at present on this important altered in their character or natural subject. We trust we have stated attributes, as by some supposed. The the case in a sufficiently lucid manindividuals which were made to sub
and we therefore now end as serve the
purposes of these novel and we began, by again putting the ques. important experiments, are preserved tion, "Reader, what is a parr ?"-"A in the Museum of the Royal Society parr, sir, is a stage or condition of of Edinburgh, where, we presume, salmon fry, intermediate between the they may be seen, on proper applicae first development of the young fish tion, by whoever desires to satisfy and the assumption of the silvery himself regarding the fact of their aspect of the smolt-the age or conactual and indisputable identity with. tinuance of that condition hovering the so-called parr.
around a maximum of about four-andBut one of the most curious as well twenty months, or thereby.”—“Quite as conclusive circumstances connected right, my fine boy: you may now sit with these later experiments, is un- down.'
NO, CCXCIV. VOL. XLVII.