150 THE ENTOMOLOGHST. 



impossibility of a renewed intercourse with the still unmodified 

 individuals of the species, will constitute first a permanent variety 

 and eventually a well-defined species. 



Satnrnia boisduvalii, Ev., from East Siberia and North Japan 

 (Graeser, Berl. Entom. Zeitschr. 1888, p. 135), also Bombyx 

 catitx, L., and B. rimicola, Hb., both from Central Europe, all of 

 which species appear as moths in the autumn and pass the 

 winter in the egg- state, may very probably have separated by 

 the operation of similar causes in past ages from the closely- 

 allied Saturniidffi and Bombycidae, which still hybernate as puj)ae. 



In this connection it may be mentioned that among the 

 Palfearctic fauna there is a widely-prevailing law that species 

 with a long pupal stage yield the perfect insect in spring or late 

 autumn, — after a period, that is to say, of coj)ious rainfall ; 

 whereas the summer fauna is almost entirely composed of species 

 which undergo a rapid development from pupa to imago. 



May the present communication be the means of setting on 

 foot many researches, which will not only serve the object of 

 filling the cabinets of entomologists with valuable specimens, 

 but will also bring welcome contributions to the study of 

 scientific Zoology. 



[Ziirich, end of August, 1894.] 



RHOPALOCERA IN THE GUILDFORD DISTRICT. 

 By W. Geover. 



As I have paid some attention to the above for several years, 

 perhaps the following remarks thereon may not be entirely 

 without interest, more especially as I have not seen any notes on 

 the Rhopalocera of this district in the 'Entomologist' for some 

 years, except a very short one (Entom. xxv. 309). The present 

 observations refer to this immediate neighbourhood only, all the 

 species mentioned having been taken — with one exception — in 

 the fields and woods to the east and within four miles of the 

 town. Although long walks in otlier directions have failed to 

 produce any additional species, I cannot claim to give anything 

 like a complete list, as I feel certain that man}^ others are to be 

 found, even within a four-mile radius, if worked thoroughly in 

 every direction by any one with more time at his disposal than 

 falls to my share. 



I regret I have been unable to make use of the excellent 

 "suggestions for recording," made in the 'Entomologist' two 

 years ago ; but, for the reason above mentioned, my chances of 

 observation are too uncertain to be of any value for the purpose 

 then suggested. 



