22 i; January, 



VESPEROCTENUS, BATES, AND ITS SYSTEMATIC POSITION. 



BY C. J. GAHAN, M.A., F.E.S., 

 OF THE BRITISH MUSEUM (nAT. HIST.). 



When Bates described this genus a few years ago (Ent. Mo. Mag., 

 1891, p. 159) he unhesitatingly referred it to the Longicornia, and 

 stated that it was, " without doubt, closely allied to our European 

 genus Vesperus^ 



But in a recent paper on the Goleoptera of Baja California [Proc. 

 Cal. Acad. Sci., ser. 2, vol. iv (1894)], to which Mr. Champion has 

 kindly called my attention, Dr. George H. Horn has had occasion to 

 treat of the genus, and has put forward an entirely different view 

 with regard to its systematic position. Placing it in the Family 

 Rhipicerid(E, Dr. Horn writes, " I never "would have suspected that 

 Mr. H. W. Bates, with whom the Ceramhycidce were a special study, 

 would have placed this insect in that Eamily." Then having given a 

 summary of the characters of the genus, Dr. Horn adds, " While I 

 greatly regret to differ so radically from my lamented friend H. W. 

 Bates in the systematic position of this insect, the aggregate of its 

 organization points to the Eamily in which it is here placed. The fact 

 that the tarsi are five-jointed removes it from association with any but 

 the most aberrant Cerambycidcs in the earlier groups of Prionides, with 

 which no one would pretend to associate this insect." In conclusion 

 of his note Dr. Horn suggests " that Vesperoctenus be placed near 

 Callirhipis, from which it differs in its twelve-jointed antennae and 

 the small fourth tarsal joint." 



After the expression of such an opinion by the foremost Coleop- 

 terist on the other side of the Atlantic, I have thought it well to 

 examine again the characters of the genus as exhibited by the single 

 male specimen in the British Museum collection, notwithstanding that 

 previous examinations gave me no ground to suppose that Bates was 

 otherwise than perfectly accurate in the position he assigned to the 

 genus. Proceeding in the light of Dr. Horn's suggestions, and com- 

 paring Vesperoctenus with Callirhipis, I find that beyond the flabellation 

 of the male antennae, and the conico-cylindrical coxse of the anterior 

 and middle legs, there is little else in common between the two genera 

 to lead one to suppose any near affinity between them. Vesperoctenus 

 has coarsely facetted eyes of a Longicorn type ; while the eyes of 

 Callirhipis and all the Shipiceridee are very finely facetted, smooth 

 and glassy looking. The scutellum of Callirhipis rises abruptly from 

 the mesonotum, forming a button-like projection fitting in between 



