ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 51 



and a neuro-intestinal anastomosis, by means of which the two primary 

 trunks communicate with one another. The ovarian tubes agree gene- 

 rally with those of the other Echiuri, and the tubes, being in the 

 specimen examined filled with ova, had a yellowish colour. Just as 

 in EcMurus, the proper covering for the egg which is found in Bonellia, 

 is completely absent. The author is unable to make any statement as 

 to the male organs. 



Echinorhynchus.* — P. Megnin states that the menisci of this 

 parasite open at the base of the proboscis by a large buccal pore ; in 

 E. brevicollis the menisci are replaced by two long cylindrical tubes 

 which open into a groove at the base of the proboscis, and extend as 

 far as the hinder extremity of the body ; they are clothed internally 

 by polygonal cells, and the whole arrangement strongly calls to mind 

 the bifurcated intestine of some Distoma. This intestine, which is to 

 be seen in encysted larvae and, undergoing atrophy, is only rej)resentod 

 by the menisci in the adults of most species, j)ersists in certain forms. 

 The author thinks that this arrangement indicates some affinity of the 

 Acanthocephali with the Trematoda, and separates them from the 

 Nematodes, with which order they are frequently placed. 



Proscolex of Eilharzia hsematobia.f— J. Chatin states that the 

 ovum is regularly oval, and has a kind of apical tubercle at one 

 pole, a character which is extremely rare among the Trematoda 

 digenea, though common enough among the T. monogenea. The 

 infusoriform character of the larva is pointed out, and the anterior 

 end is stated to become shortly differentiated into a crecum which 

 projects into the body-cavity, and which the author, agreeing with 

 Dr. T. S. Cobbold, looks upon as being the first rudiment of the diges- 

 tive tract. This being, then, possessed by the larval form, it should 

 rather be spoken of as scolex (Eedia) than as proscolex; and this 

 view would be strengthened by the certainty of the sarcode spherules 

 being, as the author thinks they are, young gemmas in course of 

 development. These amoebiform bodies are shown not to have the 

 special outer layer of the simpler organisms (AmcBbae), but rather a 

 cuticle distinctly diiferentiated, and not unlike the protecting layer 

 which we find on the young Cercarias developing within a sporocyst 

 or a Eedia. 



Nervous System of Cestoda.:}; — In the third part of his account 

 of his investigations into this system of the Platyhelminthes, Dr. A. 

 Lang deals especially with the Tetrarhynchi, which he chose on 

 account of the notorious difficulties which are associated with the 

 investigation of the Teeniadse, and because of the promise of a well- 

 developed nervous system given by the large amount of muscular 

 tissue in the scolex, and of the large size of some of the species. 

 Difficulties, however, were not evaded ; nothing of value can be 

 obtained by maceration, and nothing at all by examination of living 

 specimens. Transverse sections carefully made gave good results. 



* Oomptes Kendus, xciii. (1881) pp. 1034-6. 



t Ann. Sci. Nat. (Zool.), xi. (1881) art. No. 5, 11 pp. (1 pi.). 



t MT. Zool. Stat. Neapel, 11. (1S81) pp. 372-400 (2 pis.). 



E 2 



