THE GENUS CERCY0N. 57 



G. flavipes, F., may be separated by its black trophi (mouth 

 parts), and also by having the apices of the elytra produced into 

 a point; this is very evident if a carded specimen be held 

 sideways against the light and examined with a lens. This 

 distinction was pointed out to me by the late Mr. W. Garneys, 

 of Repton. Very common. 



C. lateralis, Marsh. — Very like the preceding at first sight, but 

 the apices of the elytra are not produced. It is usually of a lighter 

 colour, and the sides of the thorax are always broadly dull red. 

 Some people, who have not seen a type of C. aquaticus, are apt to 

 confuse it with that species, but the red margin in C. aquaticus is 

 bright, narrow, and very clearly defined, while in C. lateralis it is 

 broad and very obscure and merges into the dark colour of the 

 disc of the thorax. Common. 



The second group contains the two littoral species, C. 

 littoralis and G. depressus, which may be separated from the rest 

 of the genus by their flat, depressed, oblong shape ; they vary in 

 colour according to maturity. 



C. littoralis, Gyll., is the larger of the two and has the striation 

 of the elytra continued to the apex: it is very common on the 

 coast, especially under decaying sea-weed. 



C. depressus, Steph., is the smaller species, and has the striation 

 obliterated at the apex. It occurs in many localities on the 

 Devonshire coast, in the Isle of Wight, &c. It is not an 

 uncommon species, and is found under the same conditions 

 as the preceding. 



The third group contains three very distinct and easily 

 recognisable species, the colours being almost always constant in 

 each : C. unipunctatus, C. quisquilius, and C. melanoceplialus. 



C. unipunctatus, L., is of a light yellow colour, and on each 

 elytron is a distinct black semicircular spot, which join when the 

 elytra are closed and present the appearance of one large spot ; 

 occasionally, but very seldom, the spots are nearly obsolete. 



C. quisquilius, L., is about half the size of the preceding species, 

 which it resembles in colour, except that the elytra are immaculate. 



C. melanoceplialus, L., is of a peculiarly bright reddish orange 

 colour, with a well-marked dark triangle round the scutellum. 



All these species are very common in hotbeds and dung. 



The fourth group comprises the three smallest species of the 

 family : C. terminatus, C. pygmceus and C. nigriceps. 



ENTOM. — MARCH, 1884. I 



