QQ A]S"ATIJirA. 



wMcli present a certain degree of resemblance to recent species ; 

 but wbicb are not sufficiently similar to warrant the use of the 

 term 'identical,' or any other implying that they are of the 

 same species. 



ANASTOMA or ANOSTOMA. Fischer, (from Am, ana, back- 

 wards ; 'Zrofxci, stoma, mouth) Fam. Colimacea, Lamarck, A 

 genus of land shells so named from the singular circumstance of 

 the last whorl taking a sudden turn and throwing the mouth 

 upwards ; so as to present it on the same plane with the spire ; 

 the animal walking with the spire of the shell downwards rest- 

 ing on the foot. In other respects, these shells resemble other 

 Helices; and belong to De Ferrusac's division " Helicodonta." 

 Tomogerus is the earlier, and therefore, correct name for this 

 genus. T. depressum is represented in figs. 271, 272. The 

 nearest approach to this genus will be found in the fossil shell 

 named Eerrusina by G-rateloup, Strophostoma by Deshayes, 

 which, however, has no teeth in the aperture and is provided 

 with an operculum like Cyclostoma. South America. PL xiii. 

 figs. 271, 272. 



ANATIEER. Brug. Anatipa, Lam. This name, which signifies 

 Duckbearing, has been given to the shells commonly called Bar- 

 nacles, on account of an absurd notion entertained among the 

 ancients, that they inclose the young of the Barnacle duck, in 

 an embryo state. The beautiful bunch of jointed arms, the cilise 

 of which serve the purpose of agitating the water, so as to draw 

 in food by the current, were supposed to be the feathers of 

 the future bird. For a description of these shells, see Pente- 

 liASMis ; and fig. 34. 



ANATINA. Lam. {That which belongs to a duck) Fam. Myaria, 

 Lam. Pyloridea, Bl. — Descr. Thin, transparent, generally equi- 

 valve, inequilateral, transverse, marine ; hinge with a spoon- 

 shaped process in each valve, containing the cartilage. — Obs. 

 Some species included in the genus Anatina of authors, A. striata, 

 for instance, have not the spoon-shaped prominence, but in its 

 place a small, testaceous, moving appendage, connected with the 

 interior of the hinge. These are now separated, and form the 



