OSTEN SACKEN ON WESTERN DIPTERA. 243 



(aaa) Basal portion of the wing more or less dark ; no black spots 

 at the proximal end of the second submarginal, sec- 

 ond and third posterior cells : 

 bastardi Macq., D. E., ii, 1, p. 60. — North America. 

 pauper Loew, Centur., viii, 48. — Illinois. 

 *fur n. sp. — Texas. 

 IY. Group in which the costal cell is checkered, hyaline, and black : 



*oedipus Fab., Wied., i, p. 262 (syn. irrorata Say and 

 Macq.). 

 Schiner (Fauna Austr., Dipt., i, 52) says that the larvae of Argyra- 

 moeba live parasitically in pupse of Lepidoptera. That this is far from 

 being universally the case is proved by the fact that A. ceplius and A. 

 fur were bred from the nest of a Mud- wasp in Texas, forming tubes of 

 clay five or six inches long, pasted together like organ-pipes. The neSts 

 were found near Dallas, Tex., by Mr. Boll, and are now in the Museum 

 of Comparative Zoology in Cambridge, Mass. The pupse bored their 

 way directly through the clay, and the exuviae remained in the hole. 

 The Hymenopteron which builds these nests is very probably a Pelo- 

 pceus; the larva of the fly probably devours the larvse of the wasp. 



I observed A. cedipus in the Sierra Nevada persistently flying round 



a hole in a pine log, probably containing the nest of some Hymenopteron. 



Argyramceba leucogaster Meig. was bred from the nest of a Cemonus, 



living in deformed reeds. The article of Mr. Frauenfeld on the subject 



is well worth reading (Verh. zool.-bot. Gesellsch., 1864, 688). 



A. subnotata Meig. was bred by the same author from a nest of 

 Chalicodoma muraria Lin. (Yerh. zool.-bot. Ges. ? 1861, 173). 



A. sinuata was bred by Mr. Laboulbene from the nest of a Hymenop- 

 teron, probably Megachile muraria (see Ann. de la Soc. Entom. de 

 France, 1857, 781). 



1. Argyramceba cedipus Wied. (syn. irrorata Say, Macq.). — Seems 

 to have a very wide distribution all over North America, even quite far 

 in the northwest of the British possessions ; according to Schiner, also 

 in South America. I brought a couple of specimens from Webber Lake, 

 Sierra County, California. A specimen from the Shasta district was 



j given to me by Mr. H. Edwards. A specimen which I took in Sonoma 

 i 1 County, July 4, is larger, and the black clots in the latter part of the 

 wing are much more scarce. 



2. Argyramceba limatulus Say. — I retain under this name a group 

 I of specimens from the Geysers, Sonoma County, California (May 5-7) ; 

 j Fort Bridger, Wyoming (August 7) ; Fair Play, Colorado ; Spanish 



Peaks, Colorado ; Sangre de Cristo Mountains, New Mexico (the latter 

 collected by Lieut. W. L. Carpenter). The extent of the black on the 

 : wings in these specimens is very variable, even in those taken on the 

 1 same day and in one locality ; in many, there is very little black left 

 " except the dark clouds on the cross- veins. Whether these specimens 

 j really belong to the A. limatulus I am not prepared to affirm. Say's orig 



