356 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Uromastix acanthinurus) with large eggs most of which contain a pre- 

 cociously developed miracidium ; Opisthogenes interrogativus g. et sp. n. 

 (from the intestine of Schott's snake, Philodryas schotti), distinguished 

 by the position of the genital aperture, the shape and structure of the 

 cirrus-pouch, and the position of the yolk-glands ; and ffarmotrema 

 mfpxundum g. et sp. n. (from the intestine of Smyth's water-snake, 

 Grayia smythii) with an extremely short uterus which does not usually 

 contain more than two — relatively huge — eggs. 



Didymozoon scombri.* — Jas. Johnstone has some notes on this 

 interesting Trematode, parasitic on the roof of the mouth and about the 

 gill-region of the mackerel. In some of the cysts two worms were 

 found, coiled together inseparably, with apparent fusion in places. The 

 male organs are greatly reduced. There is a very fine efferent duct 

 opening close to the female genital orifice on the tip of the genital 

 papilla. There are no traces of prostate gland or intromittent organ. 



Proboscidian System in Nemertines.f — Gerarda AVijnhoff discusses 

 this system, which is characteristic of all Nemertines. It includes three 

 parts — the proboscis, its sheath, and the rhynchodaeum. The proboscis 

 is an introvertible tube which is fastened to the body wall at the anterior 

 end of the rhynchoccel, and is connected posteriorly by a retractor 

 muscle to the wall of the sheath. The rhynchodamm is a kind of 

 porch or atrium, through which the proboscis is everted. Both in the 

 proboscis and in the proboscis-sheath there is a muscular wall, and the 

 lumen of the sheath is lined by an endothelium. The cavity of .both 

 rhynchodreum and proboscis is lined by continuous epithelium that shows 

 a differentiation of glandular elements in different parts of the system. 

 The proboscis, therefore, consists of three layers — an epithelium, a 

 muscular coat, and an endothelial layer. The wall of the proboscis- 

 sheath consists of an endothelium and a muscular coat. The whole 

 system is embedded in the body-parenchyma. 



It has for a long time been assumed that the proboscis is a structure 

 per se, and Hubrecht supported this view. Salensky, however, founded 

 on certain embryological facts the theory that the proboscidean system 

 was comparable to the proboscis of Rhabdoc<elida proboscida. YVijnhoff 

 has gone carefully into the matter, and has studied the state of affairs 

 in many types, and is led to the conclusion that the proboscis and the 

 rhynchoceelom are both derived from the body-wall, a separation being 

 effected in the musculature. Support is thus given to Salensky's theory 

 that the proboscis of Nemerteans is homologous with that of Rhabdo- 

 ccelida proboscida. 



Incertae Sedis. 



New Variety of Rhopalura pelseneeri.J — M. Caullery describes a new 

 variety (vermiculicola) of this Orthonectid, which he found within the 

 common Nemertean Tetrastemma vermiculus in large numbers. It is a 



* Kep. Lancashire Sea Fisheries Laboratory, No. xxii. (1914) pp. 37-40 (2 pis.), 

 t Quart. Journ. Micr. Sci., lx. (1914) pp. 273-312 (36 figs.). 

 X Bull. Soc. Zool. France, xxxix. (1914) pp. 121-4 (2 figs.). 



