SUMMARY OF CURRENT RESEARCHES RELATING TO 



-limped as one species, S. meleagris ; and the fact is interesting that this 

 occurs both in the Pacific and Atlantic, but limited to American waters 

 of comparatively high temperature in both. The genus is unknown 

 elsewhere. As the same species occurs on both side of temperate and 

 Central America, Mayer is justified in saying that it has remained un- 

 changed since the closure of the Isthmus in Mesozoic times. 



American Hydroids.* — Charles Cleveland Nutting continues his 

 comprehensive monograph on American hydroids, and deals with the 

 families Campanularidae and Bonneviellidse. He gives a morphological 

 account of the Carnpanularidas, and discusses their classification, re- 

 cognizing the genera Gonothyrsea, Obelia, Obelaria, Campanula nr/, 

 Chjlia, Thaumantias, Silicularia, and Opthopyxis. The small family of 

 Bonneviellidse is marked by the presence of a well-marked " veloid " — 

 an ectodermic membrane stretching from the tentacle-bases over the real 

 oral surface, leaving a circular aperture above the true oral opening, and 

 thus forming a pre-oral cavity. Another feature is the absence of any 

 proboscis. There are four American species of Bonneviella, the only 

 genus. 



Porifera. 



Sponges of the Coasts of Ireland.f— Jane Stephens reports on the 

 Triaxonida and some of the Tetraxonicla from off the west and south- 

 west coasts of Ireland. All except Pachymatisma johnstonia were taken 

 in deep water. Five Triaxonida, eleven Tetractinellida, and twenty- 

 seven Astromonaxinellida are dealt with. Of the sixteen Triaxonida and 

 Tetractinellida, twelve are now recorded for the first time from the Irish 

 area, and Sidonops atlantica is a new species. Among the Astromonaxo- 

 nellida there are four new species— Latrumulia normcmi, Cliona coral- 

 liophaga (in Lopholielia), Laxosuberites incrustans, and L. durus ; and a 

 new genus, Atergia, is established for massive sessile Polymastidae, with- 

 out papilla, with two kinds of spicules, tylostyli and oxea, the latter 

 occurring scattered irregularly in the choanosome. 



• 



Protozoa. 



Genetics of Ciliate Protozoa. $— Clifford Dobell has written a com- 

 mentary on the genetics of Ciliate Infusorians. He begins with the 

 organization of a Ciliate and the chief events in its life. The body is 

 generally asymmetric, with anterior and posterior ends, with dorsal, 

 ventral (oral), and lateral regions, with contractile vesicles and other 

 specialized parts, with two nuclei or systems of nuclei. Multiplication is 

 usually effected by transverse fission, the meganucleus constricting, the 

 micronucleus or micronuclei dividing mitotically. Most forms are able 

 to encyst. In conjugation the protoplasm of the pair becomes con- 

 tinuous at the point of contact, aud there is a migration of micronuclear 

 elements. In Vorticella and its allies two conjugating individuals fuse 



* Bull. Smithsonian Inst. U.S. Nat. Museum, pt. 3 (1915) pp. 1-118 (27 pis. 

 and 70 figs.). 



t Sci. Invest. Fisheries, Ireland, 1914, iv. (1915) pp. 1-43 (5 pis.). 

 J Journ. of Genetics, iv. (1914) pp. 131-89 (5 figs.). 



