PUKYGANEID^E. 



621 



is very long, filiform and niultiarticulate. In Ilydropsijohe the 

 spurs are arranged thus : 2, 4, -4. Tlie antennie are rather 

 long and slender, the ocelli are absent, and the intermediate 

 feet of the female are dilated. //. scalaris Hagen is black 

 gray, with white hairs, and the antennai are jellowish, and 

 obliquely striated with black at the base ; the first joint is 

 covered with snow-white haii's. Philopotamus has three ocelli, 

 and the tibial spurs are arranged thus : 2, 4, 4. 



In RhyacophUa the maxillary palpi have the last joint entii-e. 

 straight, shorter than the rest ; while there are three ocelli, and 

 the tibial spurs are arranged thus : o, 4, 4. R. fuscida Walker 

 is rust-red, with some black hairs and a subfnscous S[)ot on 

 each side of the thorax. It comes from Hudson's Bay. 



Another curious Neuropterous insect found in the iron-stone 

 concretions of Morris, 111., is the Megathentomum pustnlatmn 

 of Scudder (Fig. 617, natural size), described and figured by 

 him in the "Palaeon- 

 tology of the Illinois 

 State Geological Sur- 

 vey." "The fragment 

 represents a wing (ap- 

 parently an upper one) 

 of a Neuropterous in" 

 sect. It is gigantic in 

 size, very broad, with 

 distant nervures, sim- 

 ple infrequent divarica- 

 tions, and in the outer 

 half of the wing, which 

 alone is presented, a 

 cross neuration, composed solely of most delicate and irrogu 

 lar veinlets. The wing is also furnished with a great number 

 of larger and smaller discolored spots, the surfaces of the 

 larger ones irregularly elevated." Mr. Scudder thinks the 

 wing IS allied to that of Coniopteryx, adding "it appears to 

 belong to a family hitherto undescribed. I do not know of a 

 single insect, living or fossil, which approaches it in the struc- 

 ture of the wings." 



Fis?. GIT. 



