1820.] Physical Science during the Year 1819. 10 



Type HI, MOLLUSCA. 



Class I, Gasteropoda. 



A most splendid work in folio, entitled, " Histoire Naturelle^ 

 generale et particuliere des MoUusques Terrestres et Fluviatiles ; 

 par le Baron de Ferussac," was published in numbers, seven of 

 which have reached England. On the sixth of March last, a 

 report was given, by the Chevalier Cuvier, on the merits of the 

 first six livraisons, to the Royal Academy of Sciences of France, 

 which must have been highly flattering to the ingenious and 

 learned author. The general intention of this magnificent 

 undertaking, which deserves the support of every zoologist and 

 geologist, is to publish in systematic order, descriptions, with 

 most correct and beautiful figures, of all the land and freshwater 

 species of shells, both fossil and recent, with their anatomy, 

 economy, and physiology. Each number contains six coloured 

 plates, with their descriptions, price in colours, 1/. 5s.; plain, 15s. 

 The first six numbers contain an account of all the species of 

 the natural family Limacidse (slugs), in the following order : 

 1. History of the family of slugs. 2. General observations on 

 the structure and faculties of the family, with an account of the 

 organisation of the foot, and of the difference that exists in the 

 respiratory cavity of such as live in water, and those which live 

 on land. 3. The habitation of those having no opercula. 

 4. The division of the order Pulmones into two families. 5. His- 

 torical account of the family Limacidae, from the most ancient 

 period of history. 6. General observations en the structure 

 and faculties of the Limacidae. 7. On the use of the Limacidae 

 in the economy of nature. 8. Synoptic table of the genera 

 which compose the family, in which four new genera are esta- 

 bhshed; namely, 1. Limacellus, of Blainville. 2. Arion. 

 3. Veronicellus, of Blainville. 4. Plectrophorus. The 

 seventh number contains the commencement of the family Heli- 

 cida;. A most favourable report has likewise been made to the 

 Royal Academy of Fine Arts by Monsieurs Van Spaendonck, 

 Desnoyers, Bervie, and Castellan. The work will be comprised 

 in 240 plates. From the vast number of figures, we do not 

 hesitate to pronounce it the cheapest work that has ever appeared 

 on any branch of zoology. 



In No. I. of the Annals of Nature, Rafinesque has estabHshed 

 a new genus named Philomicus, differing from Limax, in 

 having no visible mantle. The superior tentacula are terminal 

 and clavate; the lower ones lateral and elongated. He has 

 described four species, all of which feed on fungi. 



In the same place we find a second genus, differing likewise 

 from Limax in having no visible mantle. The four tentacula 

 ai"e cyHndrical, situated in one parallel line ; the inferior ones 

 being near to each other. Two species only are known. 



Lastly, he has described a new Limax, which he suspects 

 may form a new genus ; and a new genus of Helicid^, named 



