ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 173 



of a simple general type of the Rotatoriau ciliary wreath (most nearly 

 represented by that of Pedalioii), from which all other existing forms 

 can be readily derived by modifications closely related to the mode 

 of Hfe of the species. This general or primitive type consists of a 

 circum-apical band of fine cilia, which becomes enlarged ventrally and 

 around the mouth into a wide ciliated area called "plaque buccale "; 

 this latter may again be subdivided into supra-oral, ad-oral, and infra- 

 oral regions. The circum-apical band incloses a naked portion of the 

 frontal integument, called " plaque syncipitale," which carries sense- 

 organs, and the two openings of the retro-cerebral organ, w^hen present, 

 but never any vibratile cilia. This new conception of the morphology 

 of the wheel-organ of Rotif era deserves careful examination, as it appears 

 to possess good points, and leads to a better understanding of this organ 

 in the whole class. 



Coelentera. 



Medusae of Hawaiian Islands.* — A. G. Mayer reports on a col- 

 lection made by the ' Albatross ' off the Hawaiian Islands, but mostly 

 consisting of forms of wide distribution. Only one Scyphomedusa, 

 Charybdea moseri sp, n., appears to be peculiar to the Hawaiian region, 

 and the same is true of the Hydromedusan Solmaris insculpta sp. n. 



Fresh-water Medusae.f — Edward Potts gives a review of the known 

 facts regarding the three species of fresh-water jellyfish hitherto 

 discovered, giving a particular account of Mkrolnjdra ryderl Potts. 

 Edward T. Browne describes the medusa of Mkrohydra ryderl, and 

 compares it with Limnocodium. The young medusa has the appearance 

 of an Anthomedusa ; it is undoubtedly distinct from Limnocodium. 



Pelagic Hydroid Colonies. $ — 0. Steche discusses a hydroid colony, 

 which Chun named Perigonimuf> sidfureus, found attached to the shell 

 of Hyalma. All the nutritive individuals are concentrated beside the 

 opening of the shell ; the other areas show only medusoid Imds. There 

 is no hydrocaulis ; polyps and medusae arise singly and directly from the 

 anastomosing hydrorhiza. The medusoids exactly resemble those of 

 Perigonirmis, but the polyps are very peculiar. They are relatively very 

 large, and have a plump, barrel-like form, with 6-9 short, thick tentacles. 

 One of them showed an annular constriction in the middle, suggestive of 

 the transverse division in Protohydra. Besides nutritive polyps and 

 medusoids there were some short, conical, abortive, probably protective, 

 individuals. The coelenteron of the nutritive polyps contained molluscan 

 eggs, probably those of Hyalcea. 



New Species of Sarcophyllum from New Zealand.§ — W. B. Benham 

 gives a preliminary description of Sarcophyllum boUousi sp. n., the only 

 Pennatulid, apart from Virgidaria qracillima, that has hitherto been 

 met with in the coastal waters of New Zealand. It differs from the 

 Australian species, S. grande, in such a large number of characters that 



* Bull. U.S. Fish Commission for 1900, part iii. (1906) pp. 1131-43(3 pis.). 

 t Quart. Journ. Micr. Sci., 1. (1906) pp. 628-45 (3 pis.). 

 X Zool. Anzeig., xxxi. (1906) pp. 30-2 (2 figs.). 

 § Tom. cit., pp. 66-7. 



