SCIENTIFIC NOTES. 197 



portions of the sexes in insects, in L. dispar, at least, it is obvious that 

 an excess of <? s is by no means a necessity and probably, therefore, 

 does not occur. The actual proportion of the sexes in the experiment 

 was, of course, purely accidental, but it shewed that one male to three 

 or four females was a good working ratio. — T. A. Chapman, M.D., 

 Betula, Reigate. June 9th, 1913. 



Collective Protective Eesemblance. — In the Bulletin de la 

 Societe Entowologique de Fiance for 1913, page 137, is an article 

 by the abbe J. de .Joannis, on a collective case of protective 

 resemblance. The writer had been compiling a list of Lepidoptera- 

 Heterocera which are exclusively injurious to cultivated Mono- 

 cotyledons, such as sugar-cane, rice, maize, sago, etc., in India 

 or Java. After doing so he was struck by the fact, that out of the 

 29 species in his list, no le^s than 17 belonging to five different 

 families, had essentially the same design of markings on the wings, 

 and were thus particularly adapted to the special circumstances in 

 which their lives had to be spent. The general character of these 

 markings were longitudinal from base to outer margin of the cell, at 

 the outer extremity of which it rayed out fan-like. The transverse 

 markings were some discontinuous lines of a few dots, and the ground 

 pale yellow, dull orange, brown or whitish-yellow. All the species 

 had the lower wings very much differentiated in marking from the 

 upper ones. These insects, sitting on the stems of the plants they 

 frequented, with rayed markings such as these would no doubt be 

 admirably protected by their surroundings. At once he noticed that 

 the remaining 12 species fell into two groups, one of six species, small, 

 white, yellow or sombre in colour, uniform, without markings except 

 an inconspicuous discal dot, the other group of six species more or less 

 conspicuous, and no doubt protected in some more special way in 

 accord with their own peculiar habits. 



The species in M. de Joannis' list are: — 



NocTUiD.E. — Cirpliis loreyv', C. fra<jilis''', C. anipuncta'' , Sesamia 

 infer ens'^' , S. uniformis*. 



LYMANTRiiDiE. — Laelia si{ff'usa'''', L. adara-''-, Aroa socr«s*, Dasijc/dra 

 seciiris*. 



SpHiNGiDiE. — Leucophlebia Uneata'''. 



Euterotid^. — Dreata petola. 



Notodontid.e. — Ant icy ra combusta'^. 



PsYCHiD.E.- — Mahasejia (jraininivora^ . 



Pyralid^e. — Pohjocha saccharella''', Anerastia ahlutella\, Schoenobins 

 bipiinctifer asj, Scirpopliaga excerptalis\ , S. auriliitai, S. inonostif/inai, 

 Diatraea venosata''', Chilo simplex-'', (J. aaricilia'', C, infttscatellus'^, 

 Ancylolomia chrysographella'''', NyinpJiula fiuctuosalis, N. depunctalis, 

 Cnaphalocrocis medinalis, Morasinia trapezalis, Pyrausta coclesalis. 



Those marked * are the 17 species with similar markings; those 

 marked f are the 6 species with unicolorous forewings ; the unmarked 

 species are the 6 more or less conspicuous ones. — H.J.T. 



Divergence in the forwardness of the season in different 

 parts of Switzerland. — During a month in Switzerland, in 1912, 

 which was by no means prolific in specimens, the fact that one cannot 

 judge of the forwardness or otherwise of the season in one part of 

 Switzerland from another was more forcibly borne in on my attention 

 than has ever been the case in my long experience of that country. 



