580 KEUROPTERA. 



suborder. It agrees with most other genera of the group in 

 having a long oesophagus, which is dilated posteriorly into a 

 spacious proventriculus, which extends as far back as the fifth 

 abdominal segment. The large intestine presents a large con- 

 volution, and abruptly dilates into an oval or fusiform ccecum 

 in its lower third, which latter opens into the rectum. In 

 some genera there is a long sucking stomach inserted on one 

 of the sides. In Corydalus this is only present in the pupa, 

 and is aborted in the imago ; so also in the larva the "proven 

 triculus, with its apparatus of stomachal teeth," is adapted to 

 the carnivorous habits of the insect, but in the pupa the teeth 

 disappear, u while in the imago we find the oesophagus again 

 lengthened, still contracted at its commencement, but gradu- 

 ally dilating until it forms a capacious Florence flask-shaped 

 proventriculus, or gizzard." (See Fig. 45.) 



"With the Perli doe the gizzard is wanting, but the upper 

 extremity of the stomach has from four to eight coeca point- 

 ing forwards. With the Libellulidce the oesophagus is long 

 and large, and protrudes somewhat into the straight, oblong, 

 constricted stomach, which is without coeca, and is succeeded 

 by a very short ileum and colon. The digestive tube of the 

 EphemeridoR, which in their perfect state take no food, is 

 feebly developed. Its walls are very thin throughout, and the 

 oesophagus is directly continuous with the stomach, which is a 

 bladder-like dilation, and succeeded by a short, straight intes- 

 tine. The predatory Panorpidce, which are rapacious, differ 

 notably from the other Neuroptera, and resemble rather the 

 preceding order (Orthoptera) . The oesophagus is short and 

 straight, and in the thorax is succeeded by a spherical muscu- 

 lar gizzard which is lined internally witli a brown chitinous 

 membrane covered with stiff hairs. The stomach is tubular 

 and straight ; the ileum makes two convolutions before pass- 

 ing into the long colon." (Siebold.) In Lepisma the oesoph- 

 agus terminates in a "kind of crop, which is succeeded by a 

 globular gizzard provided with six teeth." 



There are two simple, short, salivary glands in the Sialidce, 

 while in the Phryganeidce and Hemerobidce "they'are 

 ramified and highly developed. It is quite remarkable that 

 there is, in this respect, a sexual difference with the Pan or- 



