. A manual of zoology. Zoology. 4:74 ARTIinOPODA. Increase in the difierences of environment and the correlated increase in characters lead to complete metanior|3hosis. In order to profit as much as j)ossible by its adaptation to its environ- ment the larva retains its shape as long as possible; the gradnal change is suppressed and the alteration in form necessary to the metamorphosis is postponed nntil the end of the larval life, to the period between the last two molts. In this interval there is snch an energetic transformation of the organism that the performance of ordinary vital f
. A manual of zoology. Zoology. 4:74 ARTIinOPODA. Increase in the difierences of environment and the correlated increase in characters lead to complete metanior|3hosis. In order to profit as much as j)ossible by its adaptation to its environ- ment the larva retains its shape as long as possible; the gradnal change is suppressed and the alteration in form necessary to the metamorphosis is postponed nntil the end of the larval life, to the period between the last two molts. In this interval there is snch an energetic transformation of the organism that the performance of ordinary vital functions, especially motion and feeding, is in- terfered with or rendered impossible. This last stage therefore becomes a period of rest, the jinpal stage, upon the existence of which great weight must be laid in the definition of compilete met- amorphosis. The more complete the condition of rest the more jironounced is the holometabolons develojmient. From this point of view different types of pujia? are distinguished: j)upfe libera?, pui^se obtectie, and pupias coarctata;. In a free jnipa (i")uj)a libera) the appendages stand out from the body (fig. 500), so that not. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Hertwig, Richard, 1850-1937; Kingsley, J. S. (John Sterling), 1854-1929. New York, H. Holt and Company
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1902
