154 TERTIAEY INSECTS OF NORTH AMERICA. 



Subfamily HAPHIDIID^E Stephens. 



Hitherto only one species of this group has been found in Tertiary 

 beds, and its earlier existence is unknown ; this single instance is Inoceilia 

 erigena from amber. Now, however, we find them in the rocks themselves, 

 as five species from Florissant are before us, one belonging probably to 

 Raphidia, the others to Inoceilia. This is perhaps one of the most striking 

 of the facts yet discovered in the American Tertiaries; for the known 

 species of this family not only are exclusively north temperate 1 , but almost 

 exclusively gerontogeic, the only form known from this country east of the 

 Sierra Nevadas being a (probably introduced) European species ; several, 

 however, are known from the west coast, whose insect fauna is well known 

 to have very strong European, or at least gerontogeic, affinities. A point of 

 additional interest is the fact that so many species of Inoceilia are found and 

 only one of Raphidia (and that doubtful), when Raphidia is very rich and 

 Inoceilia very poor in species at the present time. As already stated, the 

 amber species is also an Inoceilia. (September, 1883.) 



Table of the genera of Eaphidildx. 



Pterostigma crossed by veinlets and therefore composed of more than one cell ; wings three times as 



long as broad 1- RapMdia. 



Pterostigma composed of a single cell; wings more than three times as long as broad 2 Inoceilia. 



1. RAPHIDIA Linne. 



The single species referred here differs considerably from modern forms 

 in the brevity of the costal vein, the absence of costal transverse veinlets, 

 and other features of the neuration which render its reference to Raphidia 

 doubtful. It can not be referred to Inoceilia on account of the structure of 

 the pterostigma, and it should perhaps be considered as belonging to a dis- 

 tinct genus. If a true Raphidia it is the first one that has been found fossil. 



RAPHIDIA (?) TRANQUILLA. 

 PI. 14, Fig. 2($). 



A single specimea in which the head is wanting and the four wings 

 are overlapping ; the neuration is almost exactly similar in all the wings, 

 and they are of equal size, but for the sake of clearness only one of them, 

 an upper wing, has been drawn for the plate. 



1 It was by error that I alluded to these genera as indicative of a wanner climate Cor ancient Floris- 

 sant in the Annual Report of the U. S. Geological and Geographical Survey for 1878, p. 29'^. 



