. Economic entomology for the farmer and fruit-grower [microform] : and for use as a text-book in agricultural schools and colleges . Moulting of a grasshopper.—a, nymph ready to change ; b, the skin split along the back and the adult emerging ; c, continues the process, and at d, the adult insect drying out. skin alone that is affected : all the most delicate mouth parts with their hairs and processes are cast and replaced by a new cover- ing ; the lining of a large proportion of the digestive system is shed, and the inner coat or surface of the tracheal tubes is renewed, so that practically
. Economic entomology for the farmer and fruit-grower [microform] : and for use as a text-book in agricultural schools and colleges . Moulting of a grasshopper.—a, nymph ready to change ; b, the skin split along the back and the adult emerging ; c, continues the process, and at d, the adult insect drying out. skin alone that is affected : all the most delicate mouth parts with their hairs and processes are cast and replaced by a new cover- ing ; the lining of a large proportion of the digestive system is shed, and the inner coat or surface of the tracheal tubes is renewed, so that practically the insect gets, in part, a new diges- tive system and a new breathing apparatus, every time it increases in size. The number of these moults varies in the different orders, and even in species of the same order. There may be as few as three or four, and there may be twenty or more. We can some- times modify the normal number by changing the circumstances under which the insects live. Thus, the larva of the common Dermestid found in museum cases normally moults four times 4
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherphila, bookyear1896
