1922] Smith: Hatching in Neuroptera 171 



One could very clearly discern a little stream of silvery bubbles 

 of air entering the pharynx and collecting in the intestine, 

 thereby causing an observable inflation. As a result of this 

 inflation in the thoracic region, together with the shifting 

 forward of the embryo, the thin membrane parted over the 

 prothorax in the mid-dorsal line. This rent rapidly lengthened 

 to the metathorax. The larva then pushed its thorax through 

 the rent, bending its head ventrad. The thin membrane 

 slipped off the mouthparts very slowly. In a minute or so the 

 head was pulled free and the larva rested supported by the end 

 of the abdomen until the chitin hardened. After about thirty 

 minutes the larva pulled its abdomen from the molt and walked 

 away. This molt lay in a crumpled heap in the lower end of 

 the rent. The entire process of hatching from the first visible 

 movements to walking away required about forty-five minutes. 

 The egg burster (Fig. 1) is a thickening and specialization 

 of the embryonic cuticula* over the anterior part of the head 

 in the median line. The burster proper is an inverted V-shaped 

 ridge, with upper and lower lobes between which the carina 

 bends outward and is beset with about ten minute teeth or 

 irregularities. At the sides, the heavy chitinized parts are 

 continuous with the molt, but the line of demarcation can 

 generally be distinguished. 



2. Micromus posticus Walker. 



Hatching in the Hemerobiidse has been observed by the 

 writer in four species, viz., Hemerohins hiimuli, II. stigmaterus, 

 Sympherobiiis amiculus and Micromus posticus. It occurred 

 in the same way in all these species, the few differences recorded 

 are probably individual. As a type for the family, hatching in 

 Micromus posticus will be described. This species is one of the 

 most abundant in the eastern part of the United States, and 

 one of the larger ones in size. 



The chorion was observed to be entirely smooth, unsculp- 

 tured, shining and irridescent. As embryological development 

 proceeded, the outlines of the embryo could be readily seen, 

 since the chorion was very transparent. When the eggs were 

 ready to hatch, the three pairs of thoracic gray color patches 



* Smith, Roger C. The Process of Hatching in Cor3'dalis comuta Linn. 

 Annals Ent. Soc. Amer., Vol. XIII, pp. 70-74, 1920. 



