180 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Accessory Glands of the Silk-Producing Apparatus in Cater- 

 pillars.* — L. Bordas has studied the complex and very variable acces- 

 sory glands which are associated with the silk-glands in the larva of 

 many Lepidoptera, which probably serve, when functional, to agglutinate 

 or strengthen the silk threads. 



Modifications in the Development of Lepidoptera.f — Arnold 

 Pictet notes that the winter-pause exhibited by embryos, larvae, or pupa;, 

 is, in part, an expression of the hereditary constitution, for it occurs even 

 when the temperature is artificially kept from falling low. It is not 

 possible to suppress altogether the hibernal pause, but in Lasiocampa 

 quercus artificial raising of the temperature alters entirely the normal 

 duration of the various stages. 



Experiments in altering the diet of Ocneria dispar, etc., show that 

 the rate of development and the pigmentation can be greatly modified. 

 It is interesting to find that albino-forms have a pupal life shorter than 

 the normal, and that melanic forms have a pupal life longer than the 

 normal. 



In sexually dimorphic forms, bad nutrition results in regressive males, 

 like the females in colouring ; while rich nutrition results in progressive 

 females, like the males in colouring. 



Is there a Relation between Size of Eggs and Sex in Lepidop- 

 tera ? — L. Cuenot J has made observations on the sex of the progeny 

 from large and from small eggs of Bombyx mori and Ocneria dispar. 

 Both sets give rise to approximately similar numbers of males and 

 females. There seems to be no causal relation between the volume 

 of the ovum and the sex of the product. Quajat (1903) has shown that 

 there is no relation between the density of the ova of Bombyx mori and 

 the sex of the progeny. The facts, so far as they go, which is not very 

 far, tell against the theory of progamic determination of sex. 



Mosquitos of New York State. § — E. P. Felt has issued an im- 

 portant bulletin calling attention to the more important species which 

 occur in New York State, and giving keys and illustrations for their 

 identification. Special attention is given to establishing the identity 

 of both larvae and adults. Much important information concerning 

 their life histories, haunts and breeding places, their migrations, distri- 

 bution and natural enemies, is given. 



Some New Sense-Organs in Diptera.lj — W. Wesche finds that the 

 antenna? and palpi of insects are capable of receiving the stimulus of 

 several senses, and that their capacities differ greatly in different species. 

 Taste-hairs, homologous with Krsepelin's taste-hairs in Muscidas, are 

 found in various orders of insects. "What are believed to be typical 

 olfactory organs are described in Gastrophilus equi, Stratiomys chame- 

 leon, and Bibio hortidanus . Three new organs, probably sense-organs, 

 are described. 



* Cornptes Rendus, cxxxix. (1904) pp. 1036-8. 



t Arch. Bci. Phys. Nat., xviii. (1904) pp. 608-12. 



X Arch. Zool. Exper. iii. (1904), Notes et Revue, No. 2, pp. xvii.-xxii. 



§ New York State Museum, Bulletin 79 (19 241-400 (57 pis.). 



|| Jouru. Quekett Micr. Club, ix. (1904) pp. 91-104 (2 pis.). 



