216 ENTOMOLOGICAL NEWS. [September, 



Described from thirteen female and five male specimens taken 

 at Moscow, Idaho, in May, by Prof. Aldrich. 



This species is quite distinct from the described species of 



Tropidia, which are included below in the dark antennae and legs 



and the absence of the coxal spurs. The pile of the thorax and 



scutellum indistinctly longer than in T. incana Twnds. according 



to Mr. Snow, who has kindly compared them for me. 



1. nigricornis n. sp. 



2. inamillata Loew, Centur. i, 68, 1861. 



3. calcarata Will., Synopsis, 208, 1886. 



4. quadrata Say, Amer. Ent. i, viii, 1824; ibid. Comp. Wrts. Lee. i, 14. 



5. incana Townsend, Trans. Am. Ent. Soc. 1895, 52. 



6. albistyltan Macquart, Dipt. Exot. 2e, Suppl. 60, i, tab. 2, fig. 10, Will. 



Syn. 207; ibid. Ent. News, 1892, 146. 



Melanostoma rufipes Will. 



The generic position of this species has been doubtful owing 

 to the fact that only the female has been described, and that the 

 only character separating Melanostoma from Platychirus lies in 

 the anterior tarsi of the male. Dr. Williston says, "Until the 

 male of this species is known its position is somewhat doubtful. 

 Its relationship to Chilosia is very strong, but the distinctly 

 banded abdomen would seem to remove it from that genus; pos- 

 sibly it is a Platychirus." 



I have had the opportunity of examining specimens from the 

 collection of Prof. Aldrich that remove all doubt on this point. 

 The anterior tarsi of the male are not at all dilated, hence Dr. 

 Williston' s provisional location of this species in Melanostoma is 

 the correct disposition of it. It cannot be a Chilosia as there are 

 no traces of the lateral facial sutures that characterize that genus. 



These specimens show several differences from the description 

 in color; in fact none of them agrees exactly, but I am unable to 

 discover any substantial structural differences, and hence con- 

 clude that this species like the others of the genus is very variable. 



o 



ALCIDAMEA PRODUCTA Cress. AND ITS PARASITES. 

 By A. DAVIDSON, M.D., Los Angeles, Cal. 



This is one of the more common bees of this district, and may 

 be found over a wide range of territory, nesting freely wher- 

 ever convenient sites are to be found from the plains around Los 

 Angeles to at least 5000 feet altitude in the Tehachapi Mountains. 



