Page:The Zoologist, 4th series, vol 3 (1899).djvu/335

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MIMICRY.
309

with Infusoria. They had thus become almost complete vegetarians."[1]

Insects.—Numerous instances will occur to most entomologists, and are to be found scattered in entomological literature. We will again quote from other writers: "Many caterpillars, though plants are their proper food, will occasionally exhibit depravity of taste, and if kept with their own kind or with the larvæ of other moths, may turn cannibal, and make away with the company. Similarly the large green Grasshopper will eat insects smaller than itself, as well as its ordinary vegetable diet."[2] The household beetle pest Dermestes, whose larvæ not only prey on flitches of bacon, meat in larders, bladders covering jam-pots, and even books and papers, "have sometimes actually imitated the example of Anobium, and bored into wood, feeding on the timber as they advanced."[3] In various places, such as parts of India, for example, Mosquitos are found in swarms in spots never visited by human beings, and in which there are no large mammals. It has been suggested that, failing to obtain blood, Mosquitos support themselves on the juices of plants, but no observations in support of this have been recorded.[4] Even the sexes in some insects are totally diverse in the nature of their food. In the Diptera, of the families Culicidæ and Tabanidæ, according to Prof. Westwood, "it is only the females of these insects which are blood-suckers, the males being found on flowers; and Meigen discovered that the mouth of the latter sex is destitute of mandibles."[5]

Mankind.—Even man can acquire a partiality for salt or brackish water. Barrow relates that an old man in the Bokkeveld of South Africa, "who from his infancy till a few years past had lived in Zwartland, never missed an opportunity of sending thither a few bottles to be filled with the briny water for his own particular use; the pure stream of the mountain, as he asserted, not being able to quench his thirst."[6] The South Australians

  1. Eimer, 'Organic Evolution,' Eng. transl., p. 108.
  2. Badenoch, 'Romance of the Insect World,' p. 45.
  3. A.E. Butler, 'Our Household Insects,' p. 25.
  4. R.J. Pocock, 'Roy. Nat. Hist.,' vol. vi. p. 52.
  5. 'Modern Classification of Insects,' vol. ii. p. 541.
  6. 'Travels in the Interior of Southern Africa,' vol. i. p. 360.