Bulletin of the University of Texas: Scientific series, Volum 1

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University of Texas, 1907
 

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Pāgina 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.
Pāgina 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.
Pāgina 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...
Pāgina 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.
Pāgina 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...
Pāgina 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...
Pāgina 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.
Pāgina 12 - Of 109 stomachs examined, 5 contained poultry or game; 13, other birds; 46, mice; 18, other mammals; 4, frogs; 1, a lizard; 2, fish; 14, insects; 2, spiders; 9, crawfish; and 20 were empty

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