S. W. WilUston — North American Gonojndm. 389 



distinct, as in general all the organs are visible through the skin, 

 whicli is roughened with small spines. On the under side, from the 

 third segment, distinct lateral swellings are distinguishable. On the 

 last segment are two large, round or kidney-shaped stigmatic surfaces, 

 which are strongly convex, like a watch glass, and on those inner 

 border the false stigma openings appear as a clear disk. Sometimes 

 these surfaces are beset thickly with small conical warts. The anus 

 lies below. Tlie larva lies with the posterior stigmata against the 

 base of the abdomen of the insect in which it is parasitic. Between 

 the mouth booklets appear, sometimes, two additional chitinous 

 points. • The larva pupigera is oval, with button-like, slightly pro- 

 jecting anterior stigmata and with the described stigmatic plates at 

 the posterior end. Segments not sharply distinguished, skin rough 

 and with folds."* 



The larvae are parasitic upon other insects, living within the abdo- 

 men and consuming the non-vital parts. The pupal transformation 

 occurs also here, in which stage they pass the winter, escaping the 

 following spring or summer through an opening made between the 

 dorsal segments of the abdomen. From my own observations I had 

 come to the conclusion that the eggs of the parent were laid directly 

 upon the body of the insect during flight, and I afterward learned 

 that Robineau-Desvoidy Lad long before observed, as I had done in 

 Conops tibialis, a species of Conops following a Bombus, and repeat- 

 edly flying against it. They are usually parasitic upon Hymenop- 

 tera, and especially the genus Bombus. The following is a list of 

 the genera upon which they have been observed. f Conops upon 

 Oedipoda, Eucera, Haliclus, Bombus, Osmia, Vespa, Odynerus, 

 Pompilus, Sphex and Bembex ; Myopa upon Andrena and Vespa ; 

 Zodion upon Hylmxis; Stylogaster, it is thought, may be parasitic 

 upon Termites. 



CONOPS. 



Conops Linne, Fauna Suecica, p. 1797, 1761. 

 Leopoldius Rondani, Nuov. Ann. Sc. Nat. Bologna, x, 35, 1843. 

 Conopai^usV\o\\^2i.m, Gen. Ital. Conop., 1845. 

 Pleurocina Macquart, Dipt. Exot., iv, Suppl., 164, 1850. 

 Conopilla Rondani, Dipt. Ital. Prod.,i, 56, 1856. 

 Spyxosoma Rondani, Dipt. Ital. Prod., i, 56, 1856. 

 Brachyglossum Rondani, Dipt. Ital. Prod., i, 69, 1856. 

 Bombidia Lioy, Acta Venet., 3 Ser., ix, 1326, 1864. 

 Cylindrogaster\j\oy, (non Rond.), I. c. 



* Braner, Denksclir. tier matli.-natiir. Dasse der kais Acad, d Wissensch., Band 

 xlvii, p. 38, 1883. 



f Braiier, 1. c, pp. 83, 84. 



