566 SCIENCE PROGRESS 



been found in the Mesozoic rocks of Queensland. L. Lloyd 

 {Bull. Ent. Res., 12 [3], 355-9) brings to notice one of the most 

 clearly proved cases of colour response yet discovered in any 

 insect. By means of critical experiments he was able to show 

 that the Greenhouse White Fly {Asterochiton vaporariorimi) is 

 powerfully attracted to a yellow colour, and that literally 

 enormous numbers of that species can be caught by shaking 

 infested plants near a yellow screen, coated with a transparent 

 adhesive substance. Uichanco {Psyche, 28, 95-109) contributes 

 a critical paper on our present knowledge of the influence of 

 environmental factors on reproduction in aphides. This same 

 question is dealt with more fully by Davidson {Sci. Proc. Roy. 

 Dublin Soc, 16, n.s., 304-22), who shows that cytological 

 investigations on aphides and breeding experiments render it 

 highly probable that the sequence of winged and apterous 

 individuals is largely due to inherent (internal) factors. Similar 

 investigations show that the appearance of sexual forms is 

 associated with changes in the chromosome complex. F. Muir 

 {Psyche, 11 6-1 19), criticises some recent work by Crampton, 

 and discusses the phylogeny of the Homoptera. 



Lepidoptera. — ^The question of the occurrence of any in- 

 digenous species of butterfly in Iceland has been for a long 

 time under discussion. J. J. Walker {Ent. Month. Mag., 58, 

 1-7) contributes some observations on this topic, and considers 

 that there are no true native species in that island, but admits 

 the possibility that such insects, if present, may perhaps turn 

 up in one or other of its sequestered valleys. The individuals 

 of Vanessa cardui and V. atalanta that have been taken are to 

 be looked upon as stray examples of species well known to 

 possess strong migratory instincts. L. Bordas {Ann. Sci. Nat. 

 Zool., 3, 175-250) contributes an important treatise on the struc- 

 ture and Jhistology of the digestive system in adult Lepidoptera. 

 Students of genetics will be interested in two papers by Onslow 

 {Journ. Genetics, 11, 3), on the inheritance of colour and pattern 

 in Diaphora mendica and its var. rustica, and in Henierophila 

 abruptaria and the var. furcata. J. H. Gerould {Journ. Exp. 

 Zool., 34 [3], 385-412) describes a blue-green mutation in the 

 haemolymph colour of caterpillars of Colias philodice. This 

 colour is a mendelian recessive, the normal grass-green colour 

 being dominant. The adults from two blue-green larvae breed 

 true. The author concludes that the hereditary nuclear enzyme 

 (or recessive gene) involved in the case of blue-green larvae is a 

 decoloriser (inhibitor) of the yellow pigment. The eye colour 

 of the adult is affected by the mutation probably through the 

 action of the blood. It is interesting to note that parasites 

 {Apanteles) emerging from grass-green larvae spin bright golden- 

 yellow cocoons, while those emerging from blue-green cater- 



