ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 447 



Female Reproductive Organs in Ichneumonidse.* — W. Pampel has 

 made an extensive comparative study of these, and distinguishes four 

 chief types : the Ichneumon-type, the borer-type, the Ophion-tjpe, and 

 the Tri/phon-type. These differ in the shape of the ovaries ; in the 

 number of ovarioles ; in the presence or absence of uterine glands ; in 

 the state of differentiation of the receptaculum ; in the very varied 

 length of the oviducts ; and in the structure of the ovipositor. The 

 presence or absence of egg-stalks is also distinctive. 



Malpighian Tubes of Beetles.t — A. von Gorka has made an 

 anatomical and experimental study of the Malpighian tubes of Gnaptor 

 and Necrophorus, with a view to a more precise knowledge of their 

 physiological functions. In Gnaptor spinimanus there are six tubes ; 

 in Necrophorus humator four. In Gnaptor the Malpighian tubes form a 

 network on the wall of the rectum, but they do not open there. From 

 this network of tubes there arises a single thick stem, in which, however, 

 the tubes are not fused together but closely apposed. The common 

 trunk immediately divides into two branches, consisting of three tubes 

 each. These three again separate, and after taking a zigzag course 

 through the body-cavity, open at the junction of the mid-gut and hind- 

 gut. The Malpighian tubes of Necrophorus end blindly. In all the forms 

 examined the tubes opened into the mid-gut, and not into the hind-gut. 

 In Gnaptor there are, just posterior to their openings, some epithelial 

 cells which correspond in every respect to the epithelial cells of the 

 mid-gut. Behind the openings of the Malpighian tubes the large 

 sphincter dividing mid-gut from hind-gut is visible. The development 

 and disposition of the muscle-fibres of the mid-gut and hind-gut, the 

 histological structure of the Malpighian tubes themselves, and the activity 

 of the sphincter already mentioned, lead the investigator to conclude 

 that the contents of the tubes escape into the mid-gut, and that this 

 accounts for the peculiarity of the mid -gut in Gnaptor, where the 

 anterior portion of the mid-gut has an acid, and the posterior portion 

 an alkaline reaction. The histological and physiological differences 

 between the two portions of the Malpighian vessels — the network on 

 the walls of the rectum, and the free-lying tubes in the body-cavity — 

 are fully described. Experimental and chemical investigation showed 

 that physiologically the Malpighian tubes of beetles are equivalent in 

 many respects to the mid-gut glands of other Invertebrates, and that 

 their influence differs from these only in so far that, being adapted to 

 the rapid metabolism of insects, their excretory function has predom- 

 inated over their other functions of absorption, secretion, storing, etc. 



Gall-wasps and Saw-flies of Central Europe. :£ — Attention may be 

 directed to the continuation of Chr. Schroder's Insects of Central 

 Europe, an admirable work of reference. J. J. Kieffer deals with the 

 Cynipidae, and E. Enslin with the Tenthredinidte. The bulk of the work 

 is purely systematic, but the effective introductions discuss the structure, 



* Zeitschr. wiss. Zool., cviii. (1914) pp. 290-357 (3 pis. and 28 figs.), 

 t Zool. Jahrb. Abth. Allg. Zool., xxxiv. (1914) pp. 234-338 (2 pis.). 

 X Die Insekten Mitteleuropas, Band iii. Teil 3 (1914) pp. 1-213 (8 pis.) 58 and 

 75 figs.). 



