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X L. On Anisocentropus, a. new Genus of Exotic Trichoptera, 

 with Descriptions of Five Species, and of a new 

 Species of Dipseudopsis. By R. M'Lachlan, Esq., 

 F.L.S. 



[Read 2ncl February, 1863.] 



In the course of a general examination that I made some short 

 time since of the North American Trichoptera in the British Mu- 

 seum Collection, I found that the insects described by Mr. Walker 

 under under the names o? Noiidobia pyraloides, N. latifascia and 

 Go'era elegans have no connection with the genera in which they 

 have been placed, nor do they even belong to the Sericostomidce, 

 as is proved by the maxillary palpi of the two sexes being similar 

 in form, the insects of that family being readily distinguished by 

 the great difference that exists in the form of the maxillary 

 palpi in the sexes. It was evident also that the types under the 

 two last names really belonged to tlie same species, the palpi of 

 A'^. latifascia having been broken off. But what struck me most 

 forcibly was the aberrant numerical arrangement of the tibial 

 spurs, there being one spur less on the posterior than on the in- 

 termediate tibiae, a peculiarity quite singular as far as the Tri- 

 choptera are concerned. 



Dr. Hagen, in his '' Synopsis of the North American Neuroptera," 

 places the two last insects in the genus Leptocerus, quoting Mr. 

 Walker's descriptions, as he was not well acquainted with the 

 types, and retains the first in tlie genus Nolidobia. When in 

 London however, in 1861, he discovered that t'ae species were 

 wrongly placed ; but he informs me that he had not noticed the 

 aberrant arrangement of the spurs. 



There have lately been received from New Guinea and other 

 islands in the Oriental Archipelago, three other species presenting 

 the same peculiarities and otherwise generically identical, the 

 whole forming a well-marked genus, which I propose to call 

 A nisocentropus. One species, A. illustris, is perhaps the most 

 beautiful insect in the order, yet described. 



Family LEPTOCERID^. 



Anisocentropus, n. g. 

 Head convex above, ocelli absent ; antennae about twice the 



