﻿468 DR. A. VATJGHAN Olf THE FAUXAL SUCCESSION [Aug. I908, 



SpIRIFER of, CONVOLUTUS, Phill. (PI. L, fig. 4.) 



The figured fragment of a brachial valve differs in several points 

 from Phillips's type (re-figured in Davidson, pi. v, figs. 9-11). 



The fold is deeply grooved along the middle, and is strongly 

 truncated ; the flank-ribbing is suppressed, and entirely absent from 

 the greater part of the left flank ; although the early growth- 

 lines indicate sharply- acuminate cardinal angles, the angle increases 

 rapidly with age. The fine laminose foliation at the growth-lines 

 is beautifully shown, and is strikingly Athyroid. 



This remarkable shell was collected by Dr. Matley from the 

 Posidonomya-'Beds of L 6 c. 



Spiriferina 



Spiriferixa insculpta (Phillips). (PL L, fig. 9.) 



Compare Davidson, pi. yii, figs. 52-55. 



The figured fragment is a- cast of the brachial valve, and is 

 interesting as the highest record of the species — Upper Posidonomya- 

 Beds. The large size and exaggerated ornament are shown in the 

 figure. 



Martinia. 

 Martinia glabra, mut. P. (PI. L, fig. 8.) 



The form agrees with that of M. glabra, var, decora (Phill.), 

 Davidson. The sharp radiating ridges seen on the cast are charac- 

 teristic of the genus.^ 



The lozenge-shaped mesial platform, seen on the cast of the 

 pedicle-valve, indicates a deep muscular depression inside the valve, 

 and has only been observed in this late variant. The latest 

 members of many brachiopod gentes exhibit a precisely similar 

 emphasis of the muscular scars ; as, for example, Daviesiella 

 comoides, Sc7iizoj)Jioria resujnnata, etc. 



This mutation occurs only in the Upper P Beds, where it is 

 abundant at two levels (L 8p & L 9 c). 



Martinia ovaliglabra, sp. nov. (PI. L, fig. 5.) 



Pedicle-valve as in Martinia glabra. Hinge-liue long, but less 

 than the width of the shell. 



The brachial valve has a broad gentle mesial swelling, within 

 which the mesial fold is scarcely differentiated. 



The cardinal region is free from radial ornament ; the flanks and 

 fold are divided into broad low radial ribs by a small number of 

 radial creases. The fold is very inconspicuously divided into 

 three, and there are four or five stronger ribs on each flank in the 

 young specimen figured. 



Both valves are beautifully ornamented with close-set, fine, 

 concentric growth-lines. 



1 The occurrence of a similar character in Athyris glahristria and A. i^lano- 

 sulcata .suggests that this feature is mainly dependent on form. 



