ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 55 



Laodice, Staurophora, Ptychoyena, Staurodiscus, Toxorchis, Melicertissa. 

 The character, now selected as distinctive of the family, is the presence 

 of cordyli, commonly called sensory clubs, on the margin of the 

 umbrella. A cordylus is quite distinct from marginal bulbs and 

 tubercles or sprouting tentacles and cirri. Its shape varies slightly in 

 different genera, but it always has a clear translucent appearance, with- 

 out any coloration, and is free from nematocysts. It is also without 

 otoliths and such concretions as are generally found in sense-organs. 



Gonophores of Plumularia obliqua and Sertularia operculata. * — 

 S. Motz-Kossowska refers to the general opinion that, among the 

 Calyptoblastea, Medusoids occur only in the Campanulariidae and 

 related families, such as the CampanulinidaB and some of the Lafceidas. 

 In 1902 Torrey found free gonozoids in Haleciidae ; the author has 

 found medusiform gonozoids in Plumularia obliqua Saunders (in which 

 a male Medusoid was seen to detach itself) and in Sertularia operculata L. 

 (in which the liberation of a Medusoid, almost mistakable for that of 

 the former species, is probable). 



Tubularia indivisa var. obliqua. f — F. H. Gravely found this 

 variety at Port St. Mary, Isle of Man. It is characterised by a single 

 large tentacle covering the umbrella-mouth of each female gonophore 

 and capable of moving to a slight extent. A similar form has been 

 described by Bonnevie and Swenander. The female gonophore shows 

 a single radial canal instead of four — a feature correlated with the 

 presence of the single large tentacle to the base of which the canal runs. 

 The male gonophore shows no radial canals or tentacles, but shows — 

 what the normal T. indivisa apparently does not — conspicuous sterile 

 cells in the outer layers of sperm, these cells often bearing delicate 

 processes that pass inwards towards the spadix. 



Cordylophora lacustris4 — Sven Ekman discusses the distribution 

 of Cordylophora lacustris Allman in Swedish waters. 



Porifera. 



African Fresh-water Sponges.§ — R. Kirkpatrick reports on speci- 

 mens of a new variety of Ephydatia fluviatilis L., collected by J. 

 Stuart Thomson, from a pond near Cape Town. This almost cosmo- 

 politan species has been found in Europe, Asia, and America, but is 

 now recorded for the first time from Africa. A second species, Spon- 

 gillu rerebellata Bowerbank, was obtained from a pond near Cairo by 

 Innes Bey. Thus the two commonest European species have to be 

 added to the list of African fresh- water sponges, of which 21 species 

 are known. The Cape specimen, which is named E. fluviatilis var. 

 capensis var. n., is a strongly marked variety, as regards its oxeas, 

 amphidisks, and gemmules. 



* Arch. Zool. Exper.,vii. (1907) Notes et Revue, No. 4, pp. cxiv.-xviii. (3 figs.). 



t Liverpool Marine Biol. Station, 21st Ann. Rep., 1907, pp. 15-17. 



J Arkiv. Zool., iii. (1907) pp. 1-4. 



§ Ann. Nat. Hist., xx. (1907) pp. 523-5 (11 figs.). 



