THE RESTING HABIT Of INSECTS, ETC. 9 



that we know as hybernation, in as much as it limited the food supply, 

 and rendered a period of inactivity in the tissues absolutely necessary ; 

 that its direct action was scarcely the active factor is certain, because 

 those insects Avhich can get food all the winter do not hybernate. 

 Similarly, cTstivation is probably the indirect effect of heat. Animals that 

 can get food during the hottest part of the year do not ;estivate, but those 

 that live in water, which is likely to be dried up, and which frequently 

 is dried up at the hottest period of the year, have adopted by means of 

 natural selection, a resting habit which helps them to combat the 

 absence of food, and thus prevent their extermination. It is the cold 

 and drought, however, which simply prevent them getting food. 

 Hybernation and jestivation appear, therefore, to be simply reactions, 

 which enable the animals hybernating or jestivating to meet the lack of 

 food, the latter being the direct determining factor, although its absence 

 is primarily occasioned by cold or heat. 



A Few Remarks on the Lepidoptera of Tenerife. 



By SYDNEY E. CROMPTON, F.E.S. 

 The existing information about the lepidopterous fauna of the 

 Canary Islands is either buried in large and antiquated tomes, such as 

 the Histoire Naturelle des lies Cnniries, of Messrs. Webb and 

 Berthelot, published in 1836-50, at Paris, or is scattered among 

 isolated papers and pamphlets in foreign languages, and in the 

 Transactions of various learned societies at home and abroad. Bory 

 St. Vincent's Essais Ktir les Titles Fortunces (Paris, 1805) contains 

 only a mere list of butterflies and moths. Our most recent and 

 most scientific authority on the Rhopalocera and Heterocera of the 

 Canary Islands is Dr. Rebel, whose two brochures on the subject, pub- 

 lished about a year ago, are simply invaluable. But to an English 

 lady belongs the merit of having written t/he first modern treatise on 

 the moths and butterflies of Tenerife. Mrs. Holt-White's little 

 volume, dealing in a popular manner with the Lepidoptera of Tenerife, 

 opened up the way for oUier students, and has done much to turn the 

 attention of entomologists to the Canaries, not only as a health resort 

 in winter, but also as a place where, though the insect fauna is limited, 

 the species to be found present many characteristics of extreme 

 interest to the philosophical biologist, who studies them from 

 a Darwinian standpoint, as aids to soh-ing the secret of that " far-off^ 

 divine event towards which the whole creation moves." To this fact I, 

 as a resident in Tenerife, can testify, that since the publication of Mrs. 

 Holt-White's handbook there has been a breaking out of an entomolo- 

 gical rash on the face of Canarian society, no less conspicuous than 

 astonishing. Throughout the last season in Puerto Orotava (the 

 fashionable side of the island of Tenerife) I was surprised to notice the 

 numbers of visitors who sported butterfly nets and killing bottles. 

 Some were to my knowledge earnest, scientific, and systematic 

 lepidopterologists ; but many were merely pursuing their scale-winged 

 victims (probably ignorant of their scale-wingedness !) simply from a 

 dilettante inclination, or as a relief to the ennui and lassitude of 

 Orotavian existence, to which all visitors fall a prey who come to the 

 islands without some study or hobby with which to occupy themselves 

 in the intervals of social gatherings and pleasures. 



