THE VARIATION OF SARROTHRIPUS REVAYANA, SCOPOLI. 101 



(Fig. 1), SO that the next two modifications of it can be compared 

 "with it. 



ab. atrata, n. ab. (PI. I, fig. 2.) 



In this aberration the ground colour is darker than in ab. 

 ramosana, and the black streaks and shading cover almost the 

 whole of the superiors. 



This is the darkest of the ab. ramosana forms. I have two 

 examples captured in the New Forest in 1917. Probably, in ' 

 view of the gradual darkening of many species of British 

 Lepidoptera, it represents a recent development, and may be 

 expected to become more frequent and pronounced in the future. 



ab. cladodes, n. ab. (PI. I, fig. 3.) 

 Synonymy. — Barrett, Brit. Lep. vi, pi. ccli, fig. 3c. 



Description. — Under this name I include those forms of ab. 

 ramosana which are paler than the type. 



Barrett's figure is an extremely light form; probably it repre- 

 sents the extreme xanthism of this aberration in Britain. 



ab. sagittata, n. ab. (PI. I, fig. 4.) 



This aberration has the ground colour of the superiors grey ; 

 the streak, which the figure gives the shape of, is dark fuscous ; 

 head, palpi and antennas are grey ; the thorax is grey with a 

 few fuscous scales. 



This is an exceedingly rare form, of which I have only seen two 

 or three specimens. The type is in the collection of Prof. Image, 

 to whom I am indebted for kind permission to figure and name it. 



A form very similar to this was figured in Westwood, 

 ' British Moths,' vol. ii, pi. xci, fig. 17, but the specimen 

 depicted has a red costa and hind margin to the superiors ; 

 Westwood's plates, however, are so poorly executed and different 

 in various copies that one cannot rely upon this distinction ; it 

 is described on p. 152 of the same volume ab. stonanus = ab. 

 stoninus of Curtis, which it certainly is not. This specimen was 

 taken at Birchwood. 



ab. stoninus, Curtis. (PI. I, fig. 5.) 



Syno7iymy. — ab. stonimis, Curtis, Guide, p. 203 (1829) ; Stephens, 

 Cat. Brit. Ins. vol. ii, p. 184 (1829), stonanus ; Eennie, Conspectus, 

 p. 175 (1832), stonanus ; Stephens, Haust. iv, p. 147 (1834), stonanus ; 

 Curtis, Brit. Ent. 2nd edit., No. 29 (1840); Westwood, British Moths, 

 ii, pl. xci, fig. 17, and p. 152 (1845), stonanus. 



Original description. — ab. stoninus. Superior wings brown with 

 a black branched stripe, and a waved fuscous striga across the 

 disc. Curtis, ' British Entomology,' No. 29, 2nd edition (1840). 



