SIALIDAE AND SCORPION-FLIES 



449 



at each end so as to form elongate loops ; the mesenteron is very 

 complex in character. 



A considerable number of fossil re- 

 mains from both Tertiary and Mesozoic 

 strata are referred to Sialidae ; and a 

 lar.val form from the red sandstone 

 of Connecticut has been considered by 

 Scudder to be a Sialid, and named 

 Mormolucoides articulatus, but the cor- 

 rectness of this determination is very 

 doubtful (Fig. 293). These fossils are, 

 however, of special interest as being the 

 most ancient Insect larvae yet brought 

 to light. A still older fossil, from the Car- 

 boniferous strata of Illinois called 3Iiamia 

 hronsoni, is considered by Scudder to have 

 several points of resemblance to Sialidae. 



Fia. 293. Monnolucoides 

 articulatus, larva. Trias 

 of Connecticut. (After 

 Scudder.) 



Fam. IX. Panorpidae Scorpion-flies. 



Head prolonged to form a deflexed leak, provided ivitJi palpi near 



its apex; vjings elongate and 

 narrow, shining and destitute of 

 hair, vnth numerous, slightly 

 divergent veiyis and moderately 

 numerous transverse veinlets (in 

 one genus the loings are absent). 

 Larvae provided with legs, and 

 us2ially ivith numerous prolegs 

 like the saiv -flies : hahits car- 

 nivorous. 



The majority of the members 



of this family are very readily 



T=^=fe-;^^^ distinguished by the beak -like 



^*^ front of the head, this being 



^ ^^ chiefly due to enlargement of 



Fig. 294. Panorpa communis, male. r , i i -i -, if ^ 



Cambridge. parts 01 the head itseli, and 



in a less degree to prolongation 



of the mouth-parts. The upper (or front) face of the beak is 



formed entirely by the clypeus, the labrum being scarcely 



VOL. V 2 G 



