ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 435 



the anatomy of the various systems is described iu detail. This 

 interesting form, which Grassi regards as a primitive type, is com- 

 pared with various Myriopods, with Peripaius, and with insects, but 

 a report of his conclusions must be deferred till the publication of the 

 original memoir. 



y. Prototracheata, 



Peripatus.* — Dr. E. Gaffron follows up his previous research on 

 the anatomy and histology of Peripatus by a description of the 

 reproductive organs. The species studied was P. Edwarclsii. 



A. The female reproductive organs consist essentially of two 

 cylindrical tubes, whose caecal ends form the ovaries, and the remain- 

 ing portions — the oviducts, seminal receptacles, uteri, and vagina. The 

 two ducts are in communication close to the ovary, and at the vulva. 

 The ovary is attached, in the dorsal median line, to the pericardial 

 septum by a ligament, which consists of two flat muscular bands, 

 enveloped by peritoneum, and is to be regarded as a drawn-out portion 

 of the septum. The lumen of the ovarian tubes is lined by germinal 

 ejiithelium, seated on a homogeneous tunica propria. The ova are 

 surrounded by a distinct, but thin follicle, with few nuclei. Outside 

 the tunica projjria is a layer of longitudinal muscular fibres, and out- 

 side this a peritoneal sheath, from which the tracheae penetrate 

 inwards between the muscles. The oviducts, at first in communication 

 in a transverse cavity at the end of ovary, at once assume a longi- 

 tudinal course, and exhibit, at a short distance from their origin, a 

 horseshoe-shaped diverticulum. The development of this structure — 

 the receptaculmn seminis — is described. It forms in the adult a com- 

 pressed spherical vesicle, with two ciliated ducts ; it is enveloped in a 

 loose, chitinous, peritoneal sheath, inside which a muscular layer, 

 a tunica propria, and a varied internal epithelium are observed. 

 Spermatozoa were observed in the oviduct near the entrance of the 

 two ciliated canals. The ovary is pushed forwards by the ducts, and 

 exhibits notable changes of position. The ligament exhibits a cor- 

 responding increase in length, measuring in the adult as much as 

 1 cm. It is interesting to note how in insects, the ovarian tubes aro 

 similarly connected with the pericardial septum or with the heart by 

 means of the terminal filament, which is thus homologous with the 

 ligament in Peripatus. Dr. Gaffron points out the increased interest 

 of this, in the light of Schneider's observation, that in insect larvse 

 the genital rudiment originates from a fibre of the so-called " alary 

 musculature " of the heart. 



B. The male reproductive organs. — While agreeing in general with 

 Moseley's description of the male reproductive organs in P. capensis. 

 Dr. Gaffron maintains that the proximal, tubular portion is not a 

 " prostate " gland, but really part of the testis, and indeed the 

 essential sperm-producing part. In the young Peripatus, the tubular 

 portion in no way appears as a subordinate appendage of the vesicle, 

 but the latter seems merely constricted off from the former. 



* Zool. Beitr. (Schneider), i. (1885) pp. 145-63 (3 pis.)- 



