POTA'OMMATUS. 95 



river. It is a double-brooded Butterfly, both in England and 

 on the Continent, and is met with from May to September, 



The Clifden Blue is a little smaller than P. ccrydon^ the 

 largest specimens rarely measuring an inch and a half across 

 the wings. The male is of a brilliant sky-blue above, with 

 narrow black borders, and the fringes white, spotted with black. 

 There is often a sub-marginal row of small black dots on the 

 hind-wings. The female is brown above, more or less blue at the 

 base, and with a row of sub-marginal orange spots, which border 

 the black ones on the hind-wings ; the fringes are black and 

 white, as in the male. There is a black discoidal mark on the 

 fore wings only. The under side is grey, with discoidal lunules, 

 a row of spots beyond, and a marginal row of orange spots, 

 bordered with black ones. The hind-wings have three basal 

 spots, forming, with the cciural row of eyes, nearly a circle 

 round the discoidal spot. For the differences between the 

 female and that of P. corydon, see that species (p. 92). 



In the variety P cinnus^ the spots of the under side are not 

 ocellated, and in var P. ceroiius, tlie female is blue above, 

 instead of brown The true P, dory/as^ of Denis and Schiffer- 

 miiller, with which Stephens confounded a variety of P. 

 thefisy is a European species which does not occur in the 

 north-west ; it resembles P. thetis in the shade of blue in the 

 male, but the fringes are white, and unspotted. Stephens' 

 description of his P. dorylas, which is supposed to apply to a 

 variety of P thetis^ is as follows : " The male is of a bright 

 blue above, and has a slender black marginal line as in P. 

 adonis, but the cilia are immaculate ; beneath, the anterior 

 wings are pale cinereous, and have a central transverse black 

 streak on the disc, followed by a waved row of black dots 

 faintly cinctured with whitish ; there is then a delicate inter- 

 rupted band of fulvous, terminated with a whitish margin; 

 the posterior-wings resemble these of P. adonis, but they are 



