272 Mr. C. H. T. Townsend on Diptera 



This new species certainly differs from B. spinosa, Simon, 

 the type, and hitherto the only known representative of the 

 genus, at least in having the legs strongly rufescent. B. spi- 

 7iosa (Ann. Soc. Ent. France, 1880, p. 400) was obtained 

 near Alexandria. It must be added tliat Simon gives as a 

 character for his genus the fact that the tarsi of the fourth leg 

 are bisegmented. I cannot, however, distinguish two joints 

 on these tarsi in my specimen. 



XXVI. — Contrihutions from the Neio Mexico Biological Sta- 

 tion. — No. II. (continued). On a Collection of Diptera 

 from the Lotvlands of the Rio Manila, in the State of Vera 

 Cruz. II. By C. H. Tyler Townsend, F.E.S. 



[Continued from p. 33.] 



Trichopoda. 



At least eight species of Trichopoda were secured by me, 

 one of which has already been described in Section I. 

 {T. tegulata. Towns., No. 15). In separating these forms, 

 it was discovered that the males, especially in the smaller 

 species, frequently have the tips of the foot-claws broken off, 

 some specimens not having a single claw-tip remaining. 

 But they are always broken evenly and at a uniform length, 

 so that the specimens present the appearance of being a 

 distinct form with peculiar claws. Such is, of course, not 

 the case. An examination shows that the male claws become 

 abruptly more slender just before the black hook-like tips, 

 and it is at this point that they break, leaving a straight 

 yellow claw perfectly blunt at the tip. These injuries are 

 perhaps received in pairing. 



It should be mentioned that in most Trichopodas the 

 female claws are quite evenly curved and not greatly elongate, 

 with a hook-like curve at extreme tip, and yellow with tips 

 rather widely black. In the male the claws are elongated, 

 almost straight, less conspicuously black at tips, which are 

 abruptly bent hook-like at extreme ends. The leverage of 

 the claws on the bent tips causes the fracture of the latter. 

 T. phasiana, sp. n., is a notable exception in colour of claws, 

 which are black, while the form of the claws is the same as 

 above described. In T. histrio, on the other hand, the claws 

 are not so elongate, yet nearly straight, wiiile their coloration 

 agrees with that of the other species of the genus. 



The yellow colouring of the wings, which I had previously 

 considered to be a distinctive sexual character in the male, I 



