ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 357 



less in length, and when crawling about the ease looked exactly like a 

 case of black ants, their rapid darts and pauses recalling irresistibly the 

 way ants go about. When at rest they assumed the attitude of watching 

 mantises, and appeared to be procryptically coloured. Two factors were 

 in the main concerned in effecting the likeness to an ant, namely, the 

 blackness of the underside of the abdomen, and the habit of the mantis 

 when in motion of curling the posterior half of the abdomen up like a 

 scorpion's tail. On attaining a length of 7 mm., the larvae lost their 

 ant-like look. An apparently similar case has been described by de 

 Niceville. Attention is drawn also to larvae of a Ceylonese species of 

 Phyllium which resemble a distasteful beetle, also mimicked by two bugs 

 and a moth. 



North American Species of Camponotus.* — W. M. Wheeler has 

 revised the North American species of this genus of ants, and deals with 

 21 species, 17 sub-species, and 27 varieties. The genus includes the 

 largest and most conspicuous North American ants, and also some of the 

 most abundant. It may be divided into two sections, one of which, 

 the maculatus group, contains species that nest in the ground under 

 stones or logs, or, more rarely, in obscure crater nests, whereas the other 

 section embraces all the other groups, and contains species that usually 

 nest in dead wood or oak-galls. These wood-inhabiting species, how- 

 ever, exhibit considerable diversity of habit. Apart from the circurn- 

 polar G. hercuhanus and C. fallax, all the species are decidedly local. 



Study of Sphegidse.f — A. Popovici-Baznosanu has studied Trypo- 

 xylonfigulus and Psenulus atrafus, both common insects in the Roumanian 

 rose-gardens. They have specialized predatory habits and insinuate 

 themselves into narrow tubes. The abdomen has a very narrow waist 

 and is very mobile, well adapted for stinging the victims. 



The nests of Trypoxylon in the rose-stems have partitions of earth, 

 just as in those of Osmia, which they closely resemble. There is always 

 a cocoon, and the provisions consist of spiders. 



The nests of Psenulus have parchment partitions ; there is rarely a 

 true cocoon. The provisions consist of aphides. The carnivorous larva 

 has four sharp teeth on the mandibles ; the adult has two blunt teeth, 

 suited for building. Similarly, the larva of Trypoxylon has five sharp 

 teeth and the adult only two. 



Spermatogenesis in Currant-moth.:};— L. Doncaster has investigated 

 the spermatogenesis in the two forms Abraxas gross ulariata and A. lacti- 

 color and in the heterozygote. He has already shown that in this moth 

 the glossulariata character is a Mendelian dominant, and, further, is not 

 borne by eggs which contain the female determiner. 



There are two kinds of primary spermatocytes, one set leading to 

 smaller spermatids. As these become converted into spermatozoa there 

 is evidence of nuclear degeneration. 



" From the fact that the same process occurs in both varieties, and 

 that usually the expected sexual and Mendelian ratios are found in 



* Arm. New York Acad. Sci., xx. (1910) pp. 295-354. 



f Arch. Zool. Bxper., vi. (1911) Notes et Revue, No. 3, pp. xciii-ciii. 



% Proc. Cambridge Phil. Soc, xvi. (1911) pp. 44-5. 



