1922] Smith: Hatching in Neuroptera 173 



lodged finally in the lower end of the rent of the chorion. 

 The larva rested until its legs would bear its weight, and then 

 pulled its abdomen from the egg shell and molt. The burster, 

 which is a part of the molt, could be seen with the unaided 

 eye. The entire process from the first piercing of the chorion 

 to walking away requires from 15 to 20 minutes. 



The egg burster is again a specialization of the embryonic 

 molt, but differing considerably from those of other families 

 seen. It is a toothed keel, but the upper half is free and 

 extends over the clypeal region of the head. There are no 

 prominent lobes, but the apex of the ridge bears from 15 to 20 small 

 saw-like teeth. There is a rather marked diamond-shaped 

 cap which fits over the buccal region. This cap is thought to 

 be the line of demarcation between the heavier and lighter 

 chitinization of the molt. This burster apparently resembles 

 that gf Osmylus as figured by Hagen (1852). 



3. Chrysopa oculata Say. 



Hatching in this species, and in all closely related species 

 of Chrysopidae so far seen, takes place in a manner almost 

 identical with that described for M. posticus. The chief 

 accounts seen in literature concerning hatching in this family 

 are the writings of Hagen (1859, 80) in which reference is made 

 to a cephalic saw by means of which the first opening is effected. 

 Hatching has been incorrectly described by several writers as 

 effected by the mandibles of the embryo piercing the chorion, 

 or the upper end of the egg being cut off. The position of the 

 embryo in the egg would render the first explanation, a priori, 

 impossible and in the case of the second there is no cap on the 

 egg to be lifted. 



Eggs ready to hatch show rather clearly the outline and parts 

 of the embryo, as the chorion is transparent to a considerable 

 degree. The two very prominent eyes or ocellar fields stand 

 out clearly and can be seen with the unaided eye. On the 

 ventral side in the mid-dorsal line between the eyes can be seen 

 a short, dark line. This line is the cephalic saw of Hagen, 

 or the egg burster. Just before hatching, it appears quite 

 dark or black, perhaps due to an increase in chitinization. 

 Hatching can be readily observed without a long wait by taking 

 some eggs from a cluster for observation in which most have 

 already hatched. 



