. Ants; their structure, development and behavior. head is folded over the anterior poleof the egg) and three pairs of thoracic legs, but there are also tracesof the abdominal appendages, although all of these disappear beforethe hatching of the larva. The thoracic limbs and antennre againdevelop in the larval stage, but the evanescent abdominal appendages,with the exception of those that go to form the parts of the sting ofthe adult, are mere vestiges, harking back, so to speak, to the legs ofancient larval types like the caterpillar, or cruciform larva of the saw-Hies or even to the Pakeocli
. Ants; their structure, development and behavior. head is folded over the anterior poleof the egg) and three pairs of thoracic legs, but there are also tracesof the abdominal appendages, although all of these disappear beforethe hatching of the larva. The thoracic limbs and antennre againdevelop in the larval stage, but the evanescent abdominal appendages,with the exception of those that go to form the parts of the sting ofthe adult, are mere vestiges, harking back, so to speak, to the legs ofancient larval types like the caterpillar, or cruciform larva of the saw-Hies or even to the Pakeoclictyopteroid ancestors of all insects. The larva emerges from the egg as a soft, legless, translucent grub,usually shaped like a crook-necked squash or gourd, with a broad,straight posterior and narrower, curved anterior end terminating in asmall but distinct head (Fig. 36). In some forms (Eciton, Parasyscia,Lobopelta, etc.) the body is more cylindrical (Fig. 37). In all cases,however, it consists of a head and thirteen more or less clearlv marked. FIG. 38. Larva of Stig-matonima pallipcs. (Origi-nal.) a. Larva from the side;b, flexuous hair enlarged ; c,head from above. segments. Three of these belong to the thorax, the remainder to the THE DEVELOPMENT OP AXTS. 73 abdomen, i. c., to the pedicel plus the gaster of the adult. In a fewgenera (Pscudomynna) the head, as Emery (18991) has shown, bearsminute vestiges of antennae. The mouth-parts are distinct and consistof a pair of mandibles, a pair of fleshy maxillae and an unpaired maxilke and labium are furnished with small, conical tactile-papilla; (Figs. 38-41), and the latter also bears the opening of thesericteries, or spinning glands. Xo traces of eyes are visible. Thereare ten pairs of tracheal openings, a pair each for the meso- and meta-thoracic and the eight anterior abdominal segments. The transparent chitinous integument is very thin and easilyruptured, so that handling the larvae must require considerable ca
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Keywords: ., bo, bookcentury1900, bookdecade1910, booksubjectants, bookyear1910
