MONOGRAPH 



OF 



BRITISH PERMIAN BRACHIOPOM. 



Family— TEREBRATULIM. 



Genus — Terebuatula. {Vide General Introduction, Vol. I, p. 61, 1853.) 

 Seminula, M'Coy, 1844, 1855. Epithyris, King, 1855. 



Professors M'Coy and King are of opinion that the Palaeozoic Terebratulje, T. elon- 

 gata, T. sacculus, T. hastata, T. vesicularis, and T. ficus, &c, should be generically sepa- 

 rated from Terebratula proper, such as T. vitrea, T. carnea, T. biplicata, &c, on account 

 of certain peculiarities to be hereafter described, and have respectively proposed Seminula 

 and Epithyris as generic denominations for their reception. 



The first mention of Seminula by M'Coy will be found at p. 158 of the ' Synopsis of 

 the Carboniferous Fossils of Ireland/ 1844; but the characters therein are so vaguely 

 expressed, that I did not consider it necessary to draw attention to the fact while writing 

 my General Introduction. However, as Professor M'Coy has again introduced his genus, 1 

 with different characters and types from those made use of in 1844, it will be necessary to 

 revert to the subject with some detail. 



"Genus Seminula, M'Coy, 1844. — Gen. Char. Shell small, sub-pentagonal; smooth, 

 or slightly plaited at the margin ; beak of the dorsal valve small, with a minute perfora- 

 tion ; no deltidium. The species of this genus are all small, nearly smooth shells ; the 

 margin frequently indented, but no distinct plaits on the surface ; the outline is more or 

 less pentagonal ; the beak has a very minute foramen, for the passage of the muscle of 

 attachment, but there is no deltidium separating the foramen from the hinge. This genus 

 is peculiar to the Palaeozoic rocks. Examples : S. pentahedra, Phillips, sp. ; S. pisum, 

 M'Coy ; S. rhomboidea, Phillips." 



It may, however, be observed, that none of the shells here enumerated present the 



1 'British Palaeozoic Fossils,' p. 408, 1855. 



