51 



BRACHIOPODA. 



Db. Jeffreys has recently described several species of BracJiiopoda that were 

 obtained by the deep-sea dredgings during the expeditions of H.M.S. "Lightning" 

 and *' Porcupine,'' and he has figured them in the ' Proceedings of the Zool. Soc./ 

 April 16th, 1878. One of these species, to which he has given the name of Terebratula 

 trigona, Plate xxii, fig. 3, very strongly resembles a small specimen that I found in the 

 Cor. Crag of Sutton, and which is figured in my first Supplement, Tab. xi, fig. 3 c, 

 and there considered as a young or small variety of TerebratuUtia caput serpentis, and I 

 am disposed to think that if the crag fossil could be compared with the recent shell they 

 might perhaps be specifically united. I cannot say if there be any difference in the form 

 of the loop in my specimen, as I am unable to separate the valves of the only one at 

 present known to me. I have also figured another specimen from the Cor. Crag in the 

 same plate (fig. 3 d) as capid serpentis, but this is so abnormal that when more and 

 similar specimens are found it may be perhaps entitled to specific distinction, and be 

 called anceps. At p. 169 of my first Supplement I have pointed out that the beak of 

 this latter shell has the form of that possessed by Ithynconella. In the ' Quarterly 

 Journ. of the Geol. Society,' vol. xxvii, p. 137, Dr. Jeffreys says that the Biscina from 

 the Cor. Crag is the same species as Biscina Atlantica, King ; possibly this may be so, 

 but, as in the case of the above Terebratulina, better evidence than we at present possess 

 will be necessary for the correct determination of the question. The only two specimens 

 of the Crag Biscina that I know, or have heard of, were found by myself, and these are 

 both upper valves. One of them is that figured by Mr. Davidson in 1852, also in Tab, 

 XI of my first Supplement, and is in the collection of Crag MoUusca which I gave to the 

 British Museum, and this is not perfect. The other (which is in my own cabinet) I 

 found subsequently, and in this the characters are obscured by the shell being covered 

 with a mass of Cellepora. 



