SIALID^E. 



607 



Chauliodes pectinicornis Linn., our most common species., is 

 yellowish ashen, with reddish pectinated antennae. In C. ser- 

 ricornis Say the antennae are serrate. In Corydalus, the largest 

 form known, the pro- 

 thorax is square but 

 narrower than the head 

 and the antennas are 

 stout but filiform. The 

 male of C. cornutus 

 Linn. (Fig. 594, fe- 

 male ; fig. 595, male ; 

 fig. 596, pupa; fig. 597, 

 larva), has very long 

 mandibles, about twice 

 as long as the head, 

 whence its specific 

 name. According to 

 the Editors of the 

 " American Entomol- 

 ogist," the eggs of 

 this insect (Fig. 598) 

 are "oval, about the 

 size of a radish seed, 

 and of a pale color, 

 with some dark mark- 

 ings. They are usu- 

 ally deposited in a 

 squarish mass upon 

 reeds or other aquatic 

 plants overhanging the 

 water." Hagen does 

 not " think that the 

 lateral filamentous ap- 

 pendages are connect- 

 ed with respiration ; 

 the little sponges at rig - 5!)4< 



the base of the filaments and a little behind them are the true 

 branchiae." "The reason that the larva of Corydalus has both 

 branchiae and spiracles is, that it lives, like Sialis, some weeks 

 out of the water before its transformation." (Hagen.) 



