84 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



brachial runs to the posterior margin, becoming' forked 

 beyond the middle, with the posterior branch (subanal) 

 curved, and another very faint simple vein (anal) accom- 

 panies the course of this. Halteres whitish. Abdomen 

 scarcely as long as the thorax, gradually widened behind, 

 of T segments, dusky, with a hoary bloom, and a pearly 

 gloss on the posterior segments Itypopygium as long as 

 the abdomen, and thicker, fusco-ferruginous, with 

 yellowish silky down, and composed of an oblong plate 

 below, rounded at the tip, and a pair of massive com- 

 pressed lateral arms, with a double ridge beneath, and 

 rounded at the tip, where they are articulated to a smaller 

 compressed piece, dilated at the tip, and truncated f mallet- 

 shaped)." 



The differences between the two species do not warrant 

 a minute description, and may, perhaps, be best shown in 

 synoptical form. 



Antennary shaft bicolorous, the first and last joints 

 white, the eight intervening ones brown ; thorax brown, 

 with a long median longitudinal band of a brighter colour 

 and traversed down its centre by a brownish line; 

 scutellum whitish green with a brown transverse 

 marking; wings with a faint vein between the " anal 

 and " podobrachial " veins; abdomen green, slightly 

 longer than the claspers C. bicolor. 



Antennary shaft whitish throughout; wings with no 

 vein between the "anal" and " podobrachial " veins: 

 abdomen brown like the thorax and claspers, shorter than 

 the claspers- C. marinus. 



The male of Clunio bicolor was discovered by Gadeau de 

 Kerville in the Bay of Saint Martin in 1899 ; in 1900 some 

 specimens were obtained by Chevrel at Saint Briac (llle 

 et Vilaine). It has not been recorded from any other 

 localities, and through its occurrence at Port Erin I am 



