THE LIFE-HISTORY OF A LEPIDOPTEROUS INSECT. IfiS 



(Zool., vol. ii., p. 729) describes and figures as Erehia melampvs a 

 butterfly taken by INIr. Weaver in the neighbourhood of Eannocli, 

 which differed from the form which he was accustomed to call E. 

 cassio2}e and to obtain from Cumberland. In his British Butterflies 

 (p. 80) however, he admits that he was mistaken in supposing it not to 

 be identical with that, and it is not, I think, possible to make any 

 varietal separation of the two. 



Staudinger, in his famous Catalog, thus distinguishes and locates the 

 several forms, but it must not be forgotten that, at the time of the 

 l)reparation of that work at all events, he was largely ignorant of 

 British authors : — 



Epiphron. — An outer red fascia or maculge ; tlie female with white- 

 pupilled ocelli. Hab. — Hercyn. Mountains, Silesian 

 Mountains. 



Cassiopc. — Red obsolete macular ; black blind ocelli. Hab. — 

 Germany (south), Switzerland, Franco, Piedmont, 

 Hungarian Mountains et Alps, England (north), Scotch 

 Mountains. 



Nelamus. — Hardly ocellated with black. Hab. — Alps. 



Pyrenaica. — Larger ; with large ocelli. Hab. — Pyrenees. 



It will be seen that the species is localised in two distinct centres 

 (leaving this country out of the question for the moment). The type 

 form is found in the more northerly area of distribution, its chief centre 

 being the Harz Mountains, although it is also reported from the Riesen 

 Gebirge on the east, and the Vosges on the west ; cassiope, on the other 

 hand, is an Alpine butterfly. It may be contended that only these two 

 forms should be recognised as named varieties, and it must be admitted 

 that the other forms seem rather to be sub- varieties of cassiope, than 

 to be entitled to varietal rank. This question must be settled according 

 to the opinion of the individual student. In this country, both in the 

 Lake District and Scottish habitats of the species, cassiope is the pre- 

 vailing form ; the type does occur occasionally in Scotland, but rarely 

 with white pupils, although, according to Dr. Buchanan White, even 

 such are occasionally met with. It is a curious and suggestive fact that 

 Morris, who only knew the Lake District as a locality for the sjjccies, 

 nevertheless figures it with well-developed white pupils. 



1'lie Life-jJistopy of a Lcpidoptepous Iiisect, 



Comprising some account of its Morphology and Physiology. 



By J. W. TUTT, F.E.S. 



{Cmitimied from page 146). 



Chav. II. 



THE OVUM OR EGG. 



8. — On the probable existence of sex in eo(;s. — It lias been 

 suggested that the sex of imagines bred from eggs will be determined 

 l)y the conditions in regard to abundance of food or the reverse, under 

 whicli the larva? are reared ; that under a specially nutritious diet, lepi- 

 dojjtcrous larvjB tend to })roduce female imagines, Avhilst a starvation 

 diet tends to the jiruductiou of males. This pre-su}iposes a condition 



