148 TERTIARY INSECTS OF NORTH AMERICA. 



Family SIALINA Leach. 



This family is composed of two groups, each represented in our rocks. 

 As they differ somewhat remarkably in history and distribution, such gen- 

 eral remarks as can be made will appear in contrasting the statements which 

 follow xinder each. 



Subfaixiily SIALIO^E Stephens. 



The Sialidse are evidently an expiring type. A considerable number 

 of Paleozoic forms have been referred, with more or less reason, to it or its 

 vicinity, and certainly the resemblance of its modern genera to the bulk of 

 the ancient neuropteroid types is greater than can be affirmed of any otlier 

 modern group. Yet aven in the Mesozoic period we know of comparatively 

 few examples ; Hagen refers an undescribed species fi-om the Jura to Cory- 

 dalus; Westwood figures a Sialium from the Purbecks, and the species given 

 here, belonging to the disputed Laramie beds, is known only by its egg- 

 masses ; I have also shown that the larval Mormolucoides articulatus Hitchc. 

 from the Connecticut River sandstones is to be regarded as a sialid. In 

 Tertiary times, where the number of insects known is vastly increased, we 

 find no greater representation. One species only, Chauliodes prisca, from 

 the amber, is well known ; Gravenhoi'st and Burmeister speak of a Semblis 

 from amber, which may be the same as Hagen's, above mentioned ; and an 

 insect's leg from Rott has been doubtfully referred here. No species of this 

 group has been found in the American Tertiaries. So too we find the exist- 

 ing species very meager as compared with other families of Nem-optera ; 

 but that some existed in American Tertiaries can not be doubted by any 

 who will compare oixr huge living Corydalus with the still more gigantic 

 Corydalites from the Laramie beds. (September, 1883.) 



CORYDALITES Scudder. 



Corydalilea Scudder, Bull. V. S. Geol. Geogr. Surv. Terr., IV, 537 (1878). 



The egg-masses thus named were described by me in 1878, but it was 

 not until the publication of a figure of one of them in Zittel's Handbuch der 

 Palfi?ontologie, in 1885, that their existence in beds of quite similar age in 

 Europe was recognized. On this point I may quote from a letter written me 

 by the Marquis de Saporta in May, 1886 ; 



