224 



Xyela, Dalmann. 



X. IXFUSCATA. Harris's Cat. Length, 0.24, Ex. wings, 0.52 in. 

 S . Fuscous brown, almost black ; antenna? black, basal joint partly 

 covered witli pale hair ; nasus, labrum, base of mandibles, tegulse, 

 most of abdomen beneath, and the legs dull reddish-yellow ; posterior 

 tarsi blackish ; wi-ngs smoky hyaline ; cells as mferruginea ; lanceolate 

 cell large, with oblique cross line ; lower wings in this and mferrugi- 

 nea^ with three inner cells, two of them submarginal and one beneath ; 

 five spurs on each of intermediate and posterior tibise. 



One specimen in Harris's Coll. Mass. ' 



Cephus, Fabr. Latr. 



1. C. HETEROPTERUS. Harris's Cat. Length, 0.30, Ex. wings, 0.60 

 inch. ^ . Resembles C. abbreviatus, Say, except that the basal seg- 

 ments of the abdomen are obscure ferruginou||above (rufous beneath). 

 There are two pale dots on the mesothorax, and all the legs are pale 

 honey yellow ; posterior tarsi blackish. The small marginal areolet 

 of upper wing is wanting or incomplete. 



Inhabits Mass. and N. H. (H. CoD.) 

 I think it the male of C. dbhreviatus. 



2. C. INTEGER. Harris's Cat. 9 . (JiUcorms H. Cat. $ .) Length, 

 ?. 0.36, Ex. wings, 0.72 inch. ?.. Eesembles C. abbreviatus, Say. 



It differs only as follows : the three basal segments of abdomen are 

 rufous ; posterior femora blackish, tips black ; dividing nervure of 

 first marginal wing cellule complete, the whole cellule nearly covered 

 by a blackish spot beneath the stigma. The mandibles of both 

 species are large and white at base, covering the labrum. 

 Inhabits Mass. (H. Coll.) and New York. (Mr. Akhurst.) 

 The species .called Jilicornis in the Harris collection is imperfect, 

 but closely resembles the above. 



Mr. Alex. Agassiz made the following communication on 

 " The Acalephan Fauna of the southern coast of Massachu- 

 setts (Buzzard's Bay)." 



During a visit which I made at Naushon, during the month of Sep- 

 tember, I was enabled to observe a large number of Acalephs, and 

 to satisfy myself that Cape Cod is the line of division of an Acale- 

 phan Fauna entirely distinct from that of the coast north of Cape 

 Cod, as far as we know it from Acalephs observed by Professor 

 Agassiz at Nahant and Grand Manan, and from the Acalephan 

 Fauna of the coast of South Carolina as far as known from observa- 

 tions of Mc Ready and Prof Agassiz. I shall merely mention here 

 the results which I have obtained with reference to the geographical 

 distribution of the Acalephs, and reserve a more minute comparison 



