Què en diuen els usuaris - Escriviu una ressenya
No hem trobat cap ressenya als llocs habituals.
Altres edicions - Mostra-ho tot
Bulletin of the University of Texas ..., Volum 4,Edicions 25-29;Volums 24-29
Visualització completa - 1913
Bulletin of the University of Texas ..., Volum 2,Edicions 12-17;Volums 12-16
Visualització completa - 1908
adaptation annuals appear Austin average become beds beginning birds carried caterpillar cent characteristic Chisos clays close Coast Company consists contain course covered Crank-end creek cylinder diameter direction east engine factor feet flat forest formation four grass ground Head-end Heat hills hour inches indicated land latter leaves ledges less lignite limestone live Lower measure miles minute moisture mountains natural nearly nest noted observed occur pine pipe plains plants positive pounds prairie present pressure pump Rail range region relation result ridges River rock salt sand sediments seen shows side slopes soil sotol species spring steam Street stroke structure surface temperature Texas thickness tion trees University upper vegetation wasp Weight zone
Pàgina 7 - Blackbirds had been used to feed on increased prodigiously; then finding their loss in grass much greater than their saving in corn they wished again for their Blackbirds.
Pàgina 20 - ... slain would be much greater than the number given. The person referred to states that he handles, on an average, 30,000 skins per annum, of which the greater part are cut up for millinery purposes." The same article, in referring to the destruction of birds for millinery purposes on Long Island, states, that, during the short period of four months, 70,000 were supplied to the New York dealers from a single village.
Pàgina 70 - The one preeminent, unmistakable and ever present fact is variability. Variability in every particular, — in the shape of the nest .and the manner of digging it, in the condition of the nest .(whether closed or open) when left temporarily, in the method of stinging the prey, in the degree of malaxation, in the manner of carrying the victim, in the way of closing the nest, and last, and most important of all, in the condition produced in the victims of the stinging, some of them dying and becoming...
Pàgina 8 - Crows seriously damage the corn crop, and injure other grain crops, usually to a less extent. (2) They damage other farm crops to some extent, frequently doing much mischief. (3) They are very destructive to the eggs and young of domesticated fowls. (4) They do incalculable damage to the eggs and young of native birds. (5) They do much harm by the distribution of the seeds of poison-ivy, poison-sumach, and perhaps other noxious plants.
Pàgina 47 - Not only are the leaves and stems eaten, but the roots are dug up until the circles of hare ground around the burrows become wider and wider. Many other plants, some seeds, and a few insects are eaten, but to a less extent than grass. After a long season of drought or a succession of dry years it often happens that every green thing is exterminated in a prairie-dog town and the animals are forced to move on to new pastures. In a dry season I have ridden over long stretches of barren and deserted...
Pàgina 13 - It has now been conclusively shown, I think, that hawks perform an important function in maintaining in good condition the stock of game birds, by capturing the weak and sickly, and thus preventing reproduction from unhealthy parents. One of the most plausible hypotheses explanatory of the occasional outbreaks of disease among the grouse of Scotland has been the extermination of these correctives, the disease being most virulent where the game-keepers were most active in destroying what they considered...
Pàgina 14 - Ammophila procera is closing its nest it sometimes happens 'that a piece of wood is pressed down tightly, then pulled out and pressed down again, and this is repeated several times so that one might suspect that the wasp were here improvising a tool with which to tamp down the sand.