218 S. S. Buchnan — Jurassic Brachiopoda. 



applying it to this one, I take an early opportunity of altering the 

 name of the species to Bhynchonella liostraca. 



The late Dr. Davidson, whose kind assistance I have so often 

 experienced, gave capital figures in his Brachiopoda (reference 

 quoted above) of this most peculiar species. In the Inferior Oolite 

 of England there is not as far as is known any species that at all 

 approaches to this one in character, or with which it could pos- 

 sibly be confounded. The complete absence of any ribs, except just 

 at the junction of the valves at the base, has induced me to give it 

 the name of liostraca. It is an extremely rare form, and has only 

 been met with at a few places. There are probably not more than 

 eight or nine examples known. Its' horizon is the Sowerbyi zone at 

 one or two quarries near Bradford Abbas in Dorset, and near Corton 

 Denham in Somerset. 



The late Dr. Davidson, under the name bilobata, figured the types 

 of this species, both of which were collected by myself. The one 

 represented in fig. 18 I presented to Dr. Davidson, and it is now 

 probably in the Natural History Museum. 



The only species at all resembling this one with which I am 

 acquainted is Bhynch. trigona, Quenstedt, Brachiopoda, plate 40, fig. 71 ; 

 but, as I stated in first describing this species, it differs from Rh. 

 trigona in having a well-marked deepish furrow in dorsal valve, 

 no ribs at all, but only notched at base, and dorsal valve convex from 

 beak to base. 



Teeebratula euides, S. Buck. 



1883. Terebratula dorsoplana Buck., non Waagen. Proc. Dorset Nat. Hist. Soc. 



vol. iv. page 14. 



1884. Terebratula Fleischeri? Davidson, non Oppel. Brachiopoda, Palaeont. Soc. 



Proc. Appendix to Supplement, plate 19, figs. 4-4«, page 262. 



This peculiar biplicated species has been a considerable puzzle. 

 As can be seen, I referred it to Terebratula dorsoplana, Waagen ; x 

 but Dr. Davidson, in the course of correspondence with Dr. Waagen 

 on the subject, came to the conclusion that this identification was 

 incorrect, a view in which I now also concur. In fact, a comparison of 

 the beaks of the specimens as represented by Waagen and Davidson 

 will show the difference. The foramen in Waagen's figure being 

 very small, separated from the umbo, and showing the deltidium, 

 while this species possesses a large circular foramen almost touching 

 the umbo. One point that is not quite brought out in Davidson's 

 figure is the rather pinched appearance of the beak, in consequence 

 of rather prominent beak ridges and a carina down the middle of 

 the ventral valve. 



Dr. Davidson referred this species to Terebratula Fleischeri, Oppel, 

 but with this I cannot agree. Dr. Oppel 2 took as the type of his 

 Tereb. Fleischeri the specimen figured by Davidson, Jurassic Brachio- 

 poda, Pal. Soc. pi. xiii. fig. 7, which is an elongated slightly biplicated 

 shell, much longer and narrower than the one under discussion, and 

 it lacks the peculiar beak ridges and pinched appearance of the beak. 



1 Geog. Pal. Beitrage, plate 31(8), fig. 7. 



2 Oppel, Juraformation, page 497. 



