BELLEROPHON 81 



BARBATA Humphrey. Unio. Lam. 



BARNACLES. Pentelasmis, Auct. (fig. 34.) Called Anatifa, 

 by Linnaeus and Lamarck, from the ancient notion that they were 

 the eggs or embryo of the Barnacle Duck. See Anatifer. 



BASE. In all shells which are attached to sub-marine substances, 

 the base is that part of the shell which forms the point of attach- 

 ment—as for instance, the attached valve of Spondylus, the basal 

 plate of Balanus, the lower part of the peduncle of Pentelasmis ; 

 in Unattached Bivalves, the margin opposite to the umbones, 

 where the foot of the animal, or the part analogous to it, pro- 

 trudes ; in spiral univalves, the aperture, which rests on the back 

 of the animal when walking. Lamarck and some other authors 

 have used the term base as simply opposed to apex, and apply 

 it to the anterior of the aperture. 



BATOLITES. Montf. Hippurites, Auct. 



BEAK. The Apices, or points of the valves of a bivalve shell, gene- 

 rally termed Umbones, in descriptions. Also any part which is 

 rostrated or drawn out like a beak. 



BEAKED. See Beak and Rostrated. 



BEAR'S-PAW-CLAM. The common name for Hippopus maculatus, 

 a representation of which is given in the plates, fig. 156. 



BELEMNITES. Auct (BeXsfivov, belemnon, a dart, or arrow.) 

 Fam. Orthocerata, Bl. and Lam. — Descr. Straight, conical, con- 

 sisting of two parts; the external portion forming a thick solid 

 sheath, with a cavity at the base to admit the internal portion or 

 nucleus, which is mathematically conical, and is divided into 

 chambers by smooth simple septa perforated by a lateral siphon. — 

 Obs. These singular fossils, which are found in most secondary 

 beds, have long attracted the attention of philosophers as well 

 as of the ignorant, from whom they have received the various 

 appellations of Thunder-Stones, Petrified Arrows, Petrified Fingers, 

 Devil's Fingers, Spectre Candles, &c. The above description is 

 framed to include the genera Hibolithes, Porodragus, Cetocis, 

 Acamas, and Paclites of De Montfort, and Actinocamax, Stokes. 

 Fig. 466 to 468. 



BELLEROPHON. Montf. (or Belleroph'us). —Descr. Convolute, 



G 



