1865.] GEOLOGY OF NEW BRUNSWICK. 23& 



ture of the Neuropterous family Odonata, and combine with them 

 those of families remote from that, and even belonging to a dis- 

 tinct section of the Neuroptera, exhibiting to our view a synthetic 

 type which combines in one the Pseudoneuroptera and the Neu- 

 roptera, and represents a family distinct from any hitherto known. 



" Other fossil insects, found in carboniferous concretions in Illi- 

 nois and described in Silliman's Journal (N. S. xxxvii, 34), which 

 Professor Dana has kindly allowed me to examine,* also belong to 

 hitherto unrecognized families, exhibiting similar relations to these 

 in-our-day-disconnected Sections of Neuropterous insects ; and your 

 third species is a member of still another family of Neuroptera, 

 which finds its natural relations between the two described by 

 Professor Dana. 



" A fourth, of which only an important fragment was found, 

 would seem to belong to the Neuroptera, but by some peculiarities 

 of the minuter cross-veins, thrown off in the middle of the outer 

 edge of the wing, in a most irregular and unusual manner, sug- 

 gests no intimate relations with any known family, but must have 

 belonged to a group of large and weak-winged insects. 



" The fifth and last to be mentioned is of very striking interest, 

 because, while it exhibits the peculiar venation which forms the well- 

 known tympanum or stridulating apparatus of the male, in the 

 Orthopterous Locustariae (though differing somewhat from that), 

 it also most resembles the Neuroptera in all or nearly all the other 

 peculiarities of its structure, and suggests the presence in the in- 

 sect-faunae of those ancient times of a synthetic type, which united 

 the characteristics of the Orthoptera and Neuroptera, in themselves 

 closely allied ; this point, however, requires patient and severe inves- 

 tigation, and only my earliest impressions are here recorded, made,, 

 however, immediately after a close examination into the relations 

 of other fossil insects. 



" I earnestly hope that this locality, from which these remains 

 were disinterred, may receive a most careful and thorough exami- 

 nation by yourself, who have already shown so much diligence and 

 careful scrutiny in the discovery of such important and easily over- 

 looked remains. Hitherto, the study of fossil insects has been 

 mainly confined to those of much more recent date, and has re- 

 sulted in shedding comparatively little light upon geological and 

 pakeontological questions; but these few remains, coupled with the 

 pair of insects found in Illinois, induce us ardently to anticipate 

 that the future study of fossil insects, drawn from such ancient 



