142 THE ENTOMOLOGIST. 



which grows in wet places. The following is a brief description 

 of the larva : — 



Length five- eighths of an inch. The upper portion of body is 

 fairly hairy or spiny, light brown in colour, with a dorsal row of 

 deeper brown diamond-shaped marks and a series of six black 

 dots ; lateral stripe pale yellow ; head and under side of body 

 pale ashy. 



The diamond marks remind one of a "pug" larva, and the 

 black dots are very distinct and striking. The entire series of 

 metamorphoses, from the laying of the egg to the emergence of 

 the perfect insect, occupy a period of about ten months. 



[The figure at the head of this article has been drawn by 

 Mr. Frohawk, from a rough sketch made by Mr. Hodgkinson 

 some years ago. — Ed.] 



ON THE CAUSES OF VAEIATION AND ABERRATION IN 

 THE IMAGO STAGE OF BUTTERFLIES, WITH SUG- 

 GESTIONS ON THE ESTABLISHMENT OF NEW 

 SPECIES. 



By Dr. M. Standfuss, Lecturer in both Academies at Zurich. Trans- 

 lated by F. A. DixEY, M.A., M.D., Fellow of Wadham College, 

 Oxford. 



(Concluded from p. 114.) 



8. Vanessa cardui, L. (Larvae all from Ziirich.) 

 a. Warmth. 



(1) Immediately after pupation, 6 hours at 40° C. (104^ F.), 

 then 12 hours at the normal temperature (about '22° C, 72° F.), 

 then once more 6 hours at 40° C. (104° F.), afterwards at the 

 normal (about 22° C, 72° F.), until emergence in 10 — 12 days 

 after pupation. 



Out of 42 pupae, 28 butterflies came out good specimens. Of 

 these, 26 had the normal colouring, and 2 belonged to ab. elymi, 

 Ebr, ; of the remainder, 12 were crippled, 10 being normal and 

 2 ab. elipiii, Ebr., and 2 pupae perished. 



(2) Sixty hours at 36°— 37°C. (97°— 98° F.), then the normal 

 temperature up to the time of emergence, 6 or 7 days after 

 pupation. 



An extraordinarily pale form, like those presented to the 

 entomological museum of the [Ziirichj Polytechnicum from very 

 different parts of the tropics, — for instance, from the German 

 colonies in East and West Africa. 



Upper surface. — The red colouring, which in the greater 

 number of specimens takes on a brownish tinge, becomes in- 

 creased in extent on both fore and hind wing. 



