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JOURNAL OF VARIATION. 



Vol. VII. No. 8. Febeuary 1st, 1896. 



Acidalia dilutaria Hb. (holosericata, Dup.) as a British Insect. 



By G. C. GRIFFITHS, F.Z.S,. F.E.S. 



It has been suggested by Mr. Tutt that it might be of interest if 

 Mr. Front's valuable paper on the " Identification of Acidalia 

 dilutaria, Hb.," were followed by a note on the insect, as it appears in 

 its chief British locality. 



The species was first included in the British fauna in Doubleday's 

 Synoni/mic List, 1st edition, p. 19, and a record of its capture in the 

 neighbourhood of Bristol, by Mr. Sircom, is to be found in the 

 Zoologist for 1851, p. 3,288. 



Although the great majority of captures of this species have 

 taken place in this district, there are a few records of its occurrence 

 elsewhere. Respecting one of these, at Thetford, Norfolk, Mr. C. G. 

 Barrett, to whom I wrote, has kindly informed me that the one speci- 

 men captured there was taken by the Rev. Henry Williams, in whose 

 collection he examined it, and that he was fully satisfied of its 

 identity with holosericata before including it in the list of Norfolk 

 Lepidoptera. Mr. Barrett also tells me that he has heard of cap- 

 tures of this species by Rev. J. S. St. John, at Chalfont St. Peter. 

 In the Ent. Record, vol. i., p. 289, is also a record, by Miss Kimber, 

 of its occurrence at Newbury. 



The larva of this species, under the name of A. holosericata, was 

 first described by Rev. John Hellins in the Ent. Mo. Mag., Sept., 

 1868. He says that ova were supplied to him by Mr. A. E. Hudd 

 for three years in succession, until, on the third attempt, he was 

 successful in breeding the species. The larvae hatched on 25th July, 

 and fed upon rock-rose {Helianthemnm vulgaris), and their habit was 

 to congregate three or four together, near the bottom of a shoot, 

 strip it for some distance of the bark or skin, and then feed on the 

 withered leaves at the tip of the shoot as it liung down. They ceased 

 feeding during the winter, and were at all times very sluggish. They 

 moulted for the last time about the end of' ]\Iarch, spun up during 

 May, and the moth appeared from June 20th to 29th. He describes 

 the larvse as being a little over half an inch in length, and as having 

 their skin most wonderfully wrinkled and warted. Mr. George Harding 

 informs me that he has on more than one occasion bred this species, 

 and describes the hybernating larva as standing straight out from 

 the stem on which it rests, thus resembling a small dried twig. 



The bead-quarters of 4. holosericata is upon a steep slope of 



