242 THE entomologist's record. 



ture as felt must not he replied upon without observations taken by tlie 

 thermometer. 



The South London Entomological and Natural History Society 

 met on February 28th, ISi^S, when the following among other exhibits 

 were made : — Mr. Edwards : larvfe of the Dipteron, Eristalis teaax, 

 found in some water in the stump of an old apple tree. Mr. Adkin : a 

 series of Cramhns ericeUus from Sutherland ; it was stated that this 

 species differed from C. pascuelhis in always having the silvery stripe 

 narrow and even. Mr. Tutt : continental sjiecimens of Xanthia 

 ocdlaris ; he })ointed out the features that differentiated it from 

 X. gilvarjo, riz., (1) the lower part of the reniform was white; (2) the 

 nervures wei'e well dotted with white scales : (3) the apex of the wing- 

 was more pointed. On March 14th, Mr. F. A. Hall exhibited a Pierid 



butterfly (Ithomla patillu) and its Danaid mimic (Dismorphia fortnnata). 

 from Nicaragua. Mr. Sauze : a specimen of Aedipoda tartarica taken 

 among imported garden produce at Brixton. Mr. Adkin : a series of 

 Mi'lauippe hdstata from Sutherland, which were intermediate in colour 

 between the usual southern and northern forms. Mr. Frohawk : a 

 long series of Grapta c-albuin, showing both the light and dark forms of 

 tlie male and female, which had been bred from a single batch of eggs. 

 As the progeny of one brood these were most interesting. It has 

 generally been supposed that there was considerable seasonable 

 dimorphism exhibited between the specimens bred in July from May 

 ova, and those bred in October fi-om July ova. This large brood of 

 over 200 specimens l>red from 275 eggs laid in May and June, lKi:»4, 

 however, exhibited in both sexes the brightly-coloured form with pale 

 marbled undersides usually supposed to characterise the July speci- 

 mens, and also the darker-tinted form with more uniform undersides, 

 usually supposed to characterise the October specimens. It was stated 

 that only those with light-marbled undersides were seen on the wing 

 dui-ing the summer months. Mr. Tutt suggested that, since the light 

 ones appeared more generally on the wing in summer, and he was 

 under the impression that only the sjjecimens with the more uni- 

 form coloured undersides were captured after hybernation, it was 

 probable that the dark ones even of the early brood went into hyber- 

 nation at once, whilst the ligliter specimens were those that produced 

 the October l>rood. It was well known that some specimens of each 

 brocjd of V. nrticae, even if there were three broods in a season, went 

 into hybernation, and he suggested that in G. c-albnm the coloration might 

 be an outward sign of the hybernating individuals. From Mr. 

 Frohawk's remarks it appeared that they were genex'ally the last to 

 emerge, and hence took a longer period for their development. If it 

 should be found later on that the Octoljer brood produced what has 

 hitherto been considered the two seasons' forms, it would be interesting 

 to find what percentage of these were of the bright form and whether 

 such as Avere of this form would attempt to perpetuate a third brood 

 and only the dark ones go into hybernation. That so large a per- 

 centage of Mr. Frohawk's summer brood were of the dark (autumn) 

 form was highly suggestive that a large percentage were produced by 

 natural selection with 'the tendency to liybernate strongly developed, and 

 explained how in cold seasons when only a single brood occurred tlie 

 insect was not exterminated. In a year like 1SS8, fur example, a 

 second brood was impossible, and had the whole of the early brood 



