. The animal creation: a popular introduction to zoology. Zoology. 174 DIPTEEA. the air. In about a fortnight they change into pnpaB, equally active, but very diiferent in their shape, for in- stead of the respiratory tube near the tail possessed by the larva, the pupa breathes by means of two trumpet-shaped pipes af&xed to the back of the thorax. The time at length arrives when the aquatic pupa has to give birth to an insect, whose filmy wings would be spoiled by the slightest wetting. The process by which this is accom- plished affords a very interesting spectacle. The pupa having risen
. The animal creation: a popular introduction to zoology. Zoology. 174 DIPTEEA. the air. In about a fortnight they change into pnpaB, equally active, but very diiferent in their shape, for in- stead of the respiratory tube near the tail possessed by the larva, the pupa breathes by means of two trumpet-shaped pipes af&xed to the back of the thorax. The time at length arrives when the aquatic pupa has to give birth to an insect, whose filmy wings would be spoiled by the slightest wetting. The process by which this is accom- plished affords a very interesting spectacle. The pupa having risen to the surface, elevates its thorax above the water, the skin soon splits down the back and exj)oses the foreparts of the gnat, which are quickly protruded, and the gnat floating on its old skin as in a boat, extricates its T\dngs from their cases and its legs from their boots. The wings unfold themselves, and the little creature flies away to enjoy its new existence in another element. The Crane Flies (Tipula) constitute a very numerous race, some of which are nearly related to the gnats, and pass the first period of their existence in the water. In. Fig. 134.—METAMORPHOSES OF BLOOD WOKMS. their larva state they resemble little red worms, having their tails furnished with long curling filaments, some-. 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 Jones, Thomas Rymer, 1810-1880. London : Society for Promoting Knowledge
Size: 1671px × 1495px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorjo, bookcentury1800, bookdecade1860, booksubjectzoology
