CLASSIFICATION OF THE BRACHIOPODA. 



97 



Fig. 35. 



Fig. 36. 



genera. In Rhynchonella it simply consists of the homologues of the crura of the loop 

 starting from within the socket plates, which are rarely developed to any extent, offering, 

 in this respect, a striking contrast with the large size of the corresponding structures of 

 Pentameriis." But while agreeing so far with the founder of the genus, neither Mr. 

 Woodward nor myself can entirely coincide with the views expressed on the muscular 

 arrangement ; the adductor, according to my learned friend, would have been fixed to the 

 trough process of the larger valve, and to the spatula-shaped one of the smaller valve, 

 while we feel disposed to consider that the second attachment took place at or close to 

 the base of the septum in the smaller or dorsal valve ;' the spatula-shaped process serving 

 on the contrary as a visceral support ; the cardinal muscles are supposed to have been fixed 

 to the cardinal process or boss, and 

 to near the base of the septum in 

 the ventral valve. The vascular 

 system is beautifully displayed on 

 internal casts of C. multiplicata, as 

 seen in the annexed diagrams, re- 

 duced from those published in the 

 ' Monograph of English Permian 

 Fossils/ 



Geol. range. — But few species of this genus have as yet been discovered, although I 

 firmly believe their number will increase with future researches : for the present authen- 

 ticated examples are only known to occur in the Carboniferous'^ and Permian deposits. 



Examples: C. Sc/ilot/ieimi,Y. Bnch, sp. ; C. glodulina, VhiWi^s, sp.; C. multiplicata. 

 King ; and C. crumena'^. Martin, sp., according to Professor King, &c. 



Camarophoria multiplicata. 



Genus — Pentameuus, Sowerhy, 1813. 



Type—?. Knightii, Sow. Int., PI. VII, figs. 114—119. 



Anomia (part), of LinncBus. 

 Pentamerus, of the generality of Authors. 

 Terebratula (part), of some Palaeontologists. 

 Atrypa (galeata), Dalman. 

 GypiDiA (part), Dalman, 



Animal unknown ; Shell ovate, somewhat pentagonal, elongated or transverse, and 

 articulated by means of teeth and sockets, rarely with any hinge fine or area ; dental or 

 ventral valve in general the most convex, with or without a mesial fold or sinus ; beak 



^ Professor King informs me, that he considers those impressions situated on each side of the septum 

 in either valve of Camarophoria to be due to ovarian or genital organs, and refers to what is seen on a 

 specimen of R. acuminata, of which we have given a woodcut (p. 95, fig. 33.) It appears to me that the 

 rounded areas (fig. 35) on each side of the umbonal fissure, in the casts represented above, are more 

 probably the ovarian spaces. 



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