ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 47 



folium- of Viirioiis fishes, which has its first intermediate host in 

 Drelsseiisia 'pohjinorpha. He proposes a genus Gorgoderina for Trenia- 

 tode parasites of the ureter and bladder of fishes, and Oorfjoilera for 

 Trematode parasites of the bladder of frogs. The original paper is in 

 Russian, but a full summary will be found in German under the reference. 



Land Planarian in Ohio.* — L. B. Walton records the occurrence of 

 a species of Rhynchodemus at (xambier, Ohio, which differs in many 

 particulars from R. sylvaticas, the only terrestrial planarian liitherto 

 described from the United States. 



Incertse Sedis. 



Rhabdopleura.t — C. Vaney and A. Conte discuss the structure, 

 budding, and affinities of RfMhdopleara aormani. They do not find any 

 definite septum between the three regions of the animal. As to the 

 ccelom, all that can be said is that between the body-wall and the 

 internal organs there are connective cells, separated by lacuna more or 

 less developed. They do not find any collar pores or prostomial pore, and 

 they do not believe in the "■ notochord." They failed to find a cardiac 

 vesicle. There is no evidence that the so-called central nervous system 

 is really nervous. The branchial grooves cannot be homologised with 

 gill-clefts. There is no skeletal tissue. The ovary, hitherto undiscovered, 

 lies at the base of the retractile stalk and develops at the expense of the 

 axial portion of the same. The nearest affinities of Rhahdopleura are 

 with the Endoprocta. 



Larval Nephridia of Phorouis.| — Crosswell Shearer shows that in 

 the young larva of Fhoronis the nephridia develop as outgrowths of the 

 diverticula into which the ectodermic nephridial or anal pit divides, and 

 that the solenocytes arise as direct outgrowths of certain cells of the 

 sides and ends of the nephridial canals. Nephridia and solenocytes are 

 therefore of ectodermic origin. 



In early stages the nephridial canals are long and slender openings at 

 the posterior end of the larva on either side of the anus. During 

 development the canals shorten and thicken, and their external openings 

 move forward until in the Actiuotrocha larva they open behind the ring 

 of tentacles on the anterior end of the trunk, where they project inwards 

 and forwards between the preseptal coelom and the gut wall, into the 

 hsemocoelic space of the collar region. They are closed, never com- 

 municating with the blastocoelic space in which they lie. During 

 metamorphosis the canals of the larval organs persist as the canals of the 

 adult nephridia, which acquire openings into the coelom by means of 

 ciliated funnels of unknown origin. The main ccelomic cavity of the 

 larva, the body cavity of the adult, appears a little after the nephridia 

 as a small space on the dorsal side of the rectum, and is from the first 

 unpaired. Only after metamorphosis do the nephridia come inta 

 relation with it. 



* Ohio Naturalist, v. (1905) No. 3, p. 254. 



t Rev. Suisse Zool., xiv. (1906) pp. 143-83 (4 pis.). 



X MT. Zool. Stat. Neapel.xvii. (1906) pp. 487-514 (3 pis.). 



