LEONARD HASEMAN. 301 



The three genera, Perlcoma, Psychoda and Ulomyia, all have 4- 

 jointed palpi; 3-branched radial sector, forked cubitus; three anal 

 veins and with a maximum number of sixteen joints in the antennae. 

 Some of the American species have seventeen joints. 



Ulomyia is distinguished from Pericoma and Psychoda by the 

 wings having a median upwardly bellowing sinus in the males. 

 Pericoma and Psychoda are not so sharply defined. Eaton* char- 

 acterizes the old genus Psychoda as follows : 



"Male antennae 14- to 16-jointed, with nodose flagellum composed 

 of full sized joints as far as the thirteenth joint of the antenna, fol- 

 lowed by one, two or three diminutive joints and furnished with hair 

 inserted upon the symmetrical or subsymmetrical nodes in verticles 

 consisting of a series of eleven long haired verticles closely monili- 

 form, the eleventh including the diminutive joint or joints, wings 

 ovate lanceolate, acute at the end of the median vein ; subcosta 

 very short and rudimentary, ending in the radius and not linked to 

 the costa." 



Since the European species of Psychodidse are quite numerous the 

 Rev. Eaton f recently began distributing them in smaller genera. 

 The generic redistribution has not been completed, but the following 

 six genera have been distinguished in the old genus Psychoda : 

 Philosepedon, Threticus, Logima, Telmatoscopus, Xenapates and 

 Clytocerus. When it comes to distributing our species in the 

 smaller genera, as suggested by Eaton, it will evidently be necessary 

 to erect some new genera peculiar to North America. Dealing with 

 the North American species the writer thinks it would be best for 

 the present to retain the two old genera Psychoda and Pericoma. 



Six of the new species described in this paper possess the charac- 

 ters quoted above for Psychoda and have been placed in that genus. 

 The three placed in the genus Pericoma have broader wings, rounded 

 at the apex between the simple branch of the radial sector and the 

 median vein. Sycorax lanceolata Kin. is a Trichomyia ; the third 

 anal vein, ovipositor and ventral plate are not reduced as in Sycorax, 

 and the antennae in Trichomyia are 15 jointed as in Sycorax, accord- 

 ing to Eaton. In the collection received from Professor Snow the 

 writer finds a new species of Trichomyia taken in Arizona. The 

 39 species included in this paper from North America and Cuba 



« Eaton, Ent. Mo. Mag. xl, p. 57. 

 t Eaton, Ent. Mo. Mag. xl, p. 55. 



TRANS. AM. ENT. SOC. XXXIII. (38*) SEPTEMBER, 1907. 



