26 



BRITISH PERMIAN BRACHIOPODA. 



— length 10, width 14, depth 6 lines; the same without the expansions — length 6^, 

 width 8f, depth 5^ lines. 



In 1816, Schlotheim published his first illustration of the shell under description, 

 but with the mistaken idea that it belonged to the same genus and species as 

 Terebratulites lacunosus, a Jurassic shell; and in 1834 Von Buch applied to the Permian 

 shell the distinctive appellation now generally adopted. Professor M'Coy states that 

 C. multiplicata of King should be merged into the species under description, 1 and with 

 which Baron Schauroth would likewise combine C. globulina of Phillips, 2 but I am 

 not prepared to subscribe to either opinion, because specific differences appear to have 



been satisfactorily made out both by Mr. 

 Howse and Professor King. The first is a 

 much larger shell, more transversely oval, and 

 possesses a greater number of ribs ; nor have 

 I been able to discover the passages which are 

 said to connect it with the Schlotheim species ; 

 and it appears also to be distinguished from 

 C. Schlotheimi by its much narrower marginal 

 expansions (PI. II, figs. 15 and 22), a point 

 first mentioned to me by Mr. Howse. C. glo- 

 bulina is likewise a well-characterised shell, 

 more globular in shape than either of the 

 others, with only two or three ribs on the 

 mesial fold, and one in the sinus, and has not 

 hitherto exhibited marginal expansions ; but I 

 am ready to admit that certain adult examples 

 of Phillips's shell very closely resemble some 

 young individuals of that variety of C. Sclo- 

 theimi which possess only two ribs on the 

 mesial fold (fig. 19), but both are well distin- 

 guished in the adult condition. I do not, 

 therefore, perceive the advantage to be derived 

 from combining these three shells under a 

 single denomination. 



It has been supposed that Ter. superstes, 

 De Verneuil, might likewise be united to the 

 species under description, and certainly some of our British examples of C. Schlotheimi 



Y\z. 1. C. Schlotheimi. Interior of the dorsal 

 valve. 



Fig. 2. 



Schlotheimi. Interior of the ventral 

 valve. 



Adductor muscular impressions ? C. Curved processes, 

 to which were affixed the fleshy spiral arms. D. Del- 

 tidium. E. Teeth. H. Conjoined dental plates, or 

 trough-shaped process. /. Cardinal process. K. 

 Sockets. M. Marginal expansions. 0. Spatula- 

 shaped process, or visceral support? R. Cardinal 

 muscular scars ? S. Septum. 



1 ' British Palaeozoic Fossils,' p. 445. 



2 'Ein neur Beitrag zur Palaeontologie des deutschen Zechsteiugebirges,' p. 218. 

 admits three varieties — a var. multiplicata, b var. genuina, and c var. globulina. 



Baron Schauroth 



