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THE BRITISH NATURALIST. [December 



wings whitish, more yellowish towards the costa ; the costa of the 

 anterior lobe blackish-brown to the tip. VII. — VIII." (" Manual," 

 II., p. 444). The original Linnaean description is as follows : — 

 " Alucita alis patentibus fissis flavescentibus " (" Systema Naturae," 

 10th, p. 542, No. 303). In addition to this we find:— "Alae superiores 

 lineares ; linea alba, longitudinali, ut soli margines obscuriores, im- 

 maculata. Pedes albi " (" Fauna Suecica," No. 1455, pp. 370 — 371). 



Larva — Mr. Porritt has given a most complete description of the 

 larva of this species, although he unfortunately failed to rear the moths 

 from them. He writes : — "Early in the season of last year (1885*) 

 Mr. Eustace R. Bankes, of Corfe Castle, found a larva on wild thyme, 

 from which he bred a specimen of Pterop horns tetvadactylus ; so, knowing 

 my want of the species, he this year very kindly made a sp'ecial 

 search for it, the result being that on May 20th I had the pleasure of 

 receiving three specimens from him, together with several healthy 

 growing plants of the thyme on which to feed them. Length when 

 full grown, about half an inch, and of ordinary Pterophorus shape, i.e., 

 plump, stoutest in the middle, attenuated at the extremities, rounded 

 above, flatter beneath ; head small and glossy, considerably narrower 

 than the second segment ; a tuft of short hairs springs from each 

 tubercle. Ground-colour bright pea-green, when younger (i.e. previous 

 to the last moult) having a yellowish tinge ; head yellowish-green, 

 the mandibles and a spot on each side of them, brown ; the broad 

 dorsal stripe is of a considerably darker shade of green than the 

 ground-colour and is powdered on each side with greyish-white sub- 

 dorsal stripes of the same dark green colour but not so conspicuous ; 

 spiracular stripes rather broad ; yellowish-grey segmental divisions 

 and hairs white. When younger the segmental divisions are yellowish- 

 grey. Ventral surface, legs and prolegs uniformly of the bright 

 pea-green of the dorsal area. I bred no imagos as the larvae came to 

 grief during my absence in London ; but in this case.it did not much 

 matter for Mr. Bankes having fortunately reared the imago from a 

 similar larva the previous year, had thus made sure of the species. 

 Apart from that, they were too large for P. parvidactylus, the other 

 thyme-feeding species, which, moreover, Mr. Bankes believes does not 

 occur in the district " (" Entomologist's Monthly Magazine," Vol. 

 XXIII., p. 112). Mr. Bankes writes : — " I first found a larva (which 

 produced the moth referred to by Mr. Porritt) of this species in 1884 

 and two years later sent Mr. Porritt three larvae for description. I do 

 not know the exact date when I found the larva that produced the 

 moth, but as the imago emerged on June 30th, 1884 (Mr. Porritt in 

 the "Entomologist's Monthly Magazine" wrongly refers to it as 

 1885), the larvae was almost certainly found in the middle or at the 



* This should be " 1884" not «' 1885 " vide Mr. E. Bankes' notes further on. 



