Zoological Society. 295 said to be intermediate between Orchis Morio and Orchis longicornis (Desfontaines) : it is from Hy^res. — Notice of the addition of Arceu-tolohium (Viscum Oxycedri) to the French flora, by M. Requien, the well-known botanist of Avignon. Preparing for Publication. A History of the British Freshwater Algee. By Arthur Hill Hassall. This work is intended to contain a complete account of the Modes of Reproduction, Growth, Vitality, Distribution, Uses, Classification, and Species of this most extensive and interesting class of plants ; interesting from the importance and number of the physiological and anatomical facts connected with their history. It will comprise about 300 pages of letter-press and seventy plates of drawings, illustrating every species of the classes of ConfervecB and Diatomacece hitherto discovered inhabiting the fresh waters of the British Isles, almost all of which will be represented in their perfect state, or that of repro-duction. The work is to be published by subscription. Names of subscribers and communications to be addressed to the care of Mr. Van Voorst, Paternoster Row. Books Received. Die Sud Afrikanische Crustaceen : — The South African Crustacea. 4to. with Four Plates. Von Dr. Ferdinand Krauss, Stuttgard. Handbuch einer Geschichte der Natur : — Manual of a History of Nature. By Heinrich C. Bronn, Prof. Nat. Hist. Heidelberg. 2 vols, with several Plates. Elements of Natural History. By Mrs. R.Lee, illustrated with en-gravings on wood. [A very excellent manual for the instruction of youth.] PROCEEDINGS OF LEARNED SOCIETIES. ZOOLOGICAL SOCIETY. May 9, 1843. — W^liam Yarrell, Esq., Vice-President, in the Chair. The following descriptions of new species of Shells belonging to the genus Cyclostoma, by Mr. G. B. Sowerby, were read, Cyclostoma pusillum, nob., Thes. Conch, part 3. pi. 23. f. 55*. Cycl. testd orbicular i, subdiscoided ; apice spine subprominulo ; anfractibus quatuor, rotundatis, lineis incrementi solum striatis ; suturd profundd ; aperturd circulari, peritremate tenuiusculo, sub-rejlexo, postici prope anfractum ultimum subemarginato ; umbilico patulo ; operculo multispirali, extus concavo, margine canaliculate, intils nitido. Var. a. Found at the roots of shrubs and trees at Calauang, isle of Luzon, by H. Cuming. Var. b. Found under decayed leaves in the isle of Negros, by H. Cuming.