84 



RESULTS FROM (ilPSY MOTH PARASITE LABORATORY. 



Adult females freshly issued from cocoons were dissected on several 

 occasions, and fnlly developed eugs to tlie number of 15 to 20 were 

 found in the oviducts ready for oviposition. The female of this 

 species therefore may perpetuate its kind almost immediately after 

 its eclosion from the cocoon (fig. 32). It ma}^ also be parthenogenetic 

 at times, as eggs that were laid by unfertilized females in the pre- 

 ceding exjjeriments hatched freely. Not enough evidence was gained 

 to state positively Avhether unfertilized eggs always produce males, 

 but this is probably true. 



THE FIRST-STAGE LARVA. 



DESCRIPTION OF THE NEWLY HATCHED LARVA. 



The first stage of the larva of Linincriiim is characterized by 13 

 segments, including the comparatively heavily chitinized head, and 

 a long tapering ventral appendage of the last body segment. In the 



case of newly hatched larvae 

 (fig. 35) the head is about 

 one-half as long as the body, 

 excluding the tail appendage, 

 and is bent to the axis of the 

 body at an angle of about 

 45°. Its dorsal margin is 

 strongly curved, especially 

 anteriorl}^ ; the ventral mar- 

 gin is much shorter and only 

 slightly curved. The integu- 

 ment of the head is rather 

 heavily chitinized and is 

 slightly pigmented with 

 brown. It has a slight ridge on each side running backward from 

 the insertion of the mandibles, and separating the gula from the 

 cheeks. The gula seems to be but slightly hollowed out and is as 

 heavily armored as the rest of the head. 



The mouthparts (fig. 37) consist of prominent, curved and sharply 

 pointed mandibles, crossing each other at the tips, and projecting 

 somewhat downward into the large mouth cavity. The aperture 

 of the mouth is surrounded by a raised, chitinized, circular rim, about 

 0.037 mm. in diameter, and with a broad inner margin. The poster- 

 ior inner margin is a heavily chitinized plate, with two prominent 

 teeth separated by an angular median indentation. 



The body in the thoracic region is nearly as broad as the head 

 but rapidly tapers posteriorly. The thin, delicate, transparent i?^- 

 tegument is thrown into folds on the dorsum and venter, but ajipa^" 



Pig. 35. — Limnenum validum: First-stacfe larva, 

 newly hatched. Enlarged about 120 times. 

 (Original.) 



