ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 287 



Other tissues are not coloured. The protective vahie to the hirva among 

 the violet stamens of the flower is very obvious. 



Structure of Woolly Aphis.* — J. Davidson gives a detailed account 

 of the structure of the apterous viviparous female of ScJtizoneura Jaiiigera, 

 the woolly aphis of the apple tree. He deals with the wax-secreting 

 glands, the cornicles (often misnamed " honey-tubes "), the other 

 external features, the food- canal, the nervous system, the muscles, the 

 gonads, and other internal structures. 



Absorption of Spermatozoa in Pomace Fly.t — E. Guy^not points 

 out that an inseminated female of DrosophiJa ampeJophila can go on 

 laying fertile eggs for a month or more. One insemination suffices for 

 several hundred ova. But this only happens when the female is well 

 fed. In bad conditions the spermatozoa seem to deteriorate and the 

 eggs then abort, or the spermatozoa are absorbed and the eggs develop 

 parthenogenetically. 



First Maxilla of Dipseudopsis.J — Bruce F. Cummings .describes 

 the peculiar mouth-parts of this Trichopteran genus. The long tapering 

 lobes of the first pair of maxillae are extraordinary, e.g. in their peculiar 

 sense-organs, plate-like structures of two sizes. The bearing of these 

 mouth-parts on the question of the relationship between Trichoptera and 

 Lepidoptera is briefly discussed. 



Remarkable Gall-producing Psyllid from Syria.§— R. Xewstead 

 and Bruce F. Cummings describe an extraordinary pod-shape;l gall 

 (180 mm. long, 2 mm. thick), found in the Lebanon on a twig of what 

 was in all probability the tamarind. The hollow " pod " contained an 

 immense quantity of small " mealy " Psyllids — larva? and pupa? — of a 

 species belonging i)robably to the sub-family Triozinte. Xo further 

 specimens were procuraV)le, and it is probably a rarity in the district 

 where it was found. The immense gall produced by the horde of 

 Psyllids is not only strikingly characteristic, but much larger than that 

 of any other known gall-producing Psyllid. 



Chromatin in Oogenesis of Orthoptera.|l — J. Yesely has found, in 

 studying the changes of the chromosomes during the history of the 

 germ-cells in Orthoptera, that the chromosomes are not homogeneous as 

 is often supposed. They are composed of two substances. There is a 

 spiral twisting of the chromatin around a linin axis. The chromatin 

 spiral thread is the chromonema of Yejdovsky. At the transition to 

 the second growing period in the oogenesis, the chromonemes coalesce 

 into a nucleolus-like body, and out of this again there is differentiated 

 tlie last generation of chromosomes or strepsonemes. 



* Quart. Journ. Micr. Sci., Iviii, (1913) pp. 65:3-701 (5 pis. and 4 figs.). 



t C.R. Soc. Biol. Paris, Ixxiv. (1913) pp. 389-91. 



X Ann. Nat. Hist., xi. (1913) pp. 308-12 (4 figs.). 



§ Ann. Nat. Hist., xi. (19J3) pp. 306-8 (4 figs.). 



ll Resumes Communications, 9e Congres Internat. Zool., 1913, p. 13. 



