146 [December, 



C. TJNILTNEATA, Zett. 



This species closely resembles the last ; it is usually, howercr, rather smaller 

 and more slender. The eyes are rather more widely separated in the males and 

 much further apart in the females than those of A. buccata ; the space between 

 them in the latter sex being equal to about one-fourth of the width of the head. 

 The transverse veins of the wings are usually very sinuous, especially in the males ; 

 and the hind tibiae of the same sex are furnished with a tuft or series of soft hairs in 

 the middle of their inner sides. 



Not common. I captured both sexes in 1875, at Bowdon,in Cheshire, while on 

 a visit to my friend, Mr. B. Cooke, and I have also received specimens from his own 

 collection. 



C. ALBESCENS, Zett. 



This species resembles the two preceding ones in form and colour ; it is, however, 

 usually of a much smaller size, though it varies greatly in magnitude. There appear 

 to be two distinct varieties, one as large again as the other ; the former measuring 

 5 to 6 mm. (2 J to 3 lin.), and the latter only about 3 mm. The chief characteristic 

 feature is the sub-plumose arista, on account of which Rondani placed it in a dis- 

 tinct genus {Sammomyia) . The position of the eyes is much the same as in C. 

 unilineata, but they are usually rather more widely separated in both sexes than in 

 that species. The legs have the fore tibiae ciliated along their outer sides with short 

 hairs, in the males of the larger variety ; and the hind tibioe are also furnished with 

 soft hairs on their inner and front sides. 



Found in sandy places, but not common. 



C. AREJfOSA, Zett. 



This well-marked little species is rather aberrant in its characters, for while it 

 has the face very prominent, and resembles in its general features and habits the 

 other species in this section, it differs from them all by having the abdomen de- 

 pressed or flattened at the base, but thickened at the apex by the presence of large 

 sub-anal male appendages. The eyes of the males are sub-contiguous, and those of 

 the females widely separated. The hind tibias of the former are armed along the 

 whole length of their inner sides with rigid hairs or bristles of moderate and even 

 length. The colour, especially on the thorax, is very pale, almost white. 



Rare or rather local. It chiefly frequents marine sand-hills. The only speci- 

 mens that I have seen were given to me by Mr. B. Cooke, and were taken by him at 

 Southport, in Lancashire, where it is not uncommon. 



C. IMPTJDICA, Eond. 



This species is characterized by the males having two large sub-ventral lobes on 

 the penultimate segment of the abdomen, armed with minute black spines, and with 

 a reddish spot at their base. The eyes are sub-contiguous in the males, and widely 

 separated in the females. The thorax is bristly, of a darkish grey colour, with a 

 central and two narrow irregular lateral black stripes ; the sides are cinereous. The 

 abdomen is hairy, light grey, with an interrupted longitudinal dorsal stripe ; the 

 portions of wliich are often dilated into triangular spots. The legs are furnished 

 with manv hairs and bristles, but the hind tibioe have few or none on their inner 



