﻿Vol. 66.~] SPECIES OF AMMONITES AND BRACHIOPODA. 95 



Distinctio n. — From Bradfordia liomplidla or Br. costata, 

 the smaller and deeper umbilicus, which gives to the central area 

 a quite distinct appearance. The whorl is stouter than that of 

 Br. liomphala, but almost as stout as that of Br. costata ; the 

 degree of costation, however, agrees with that of the former. 



Locality and stratum. — Stoke Knap (Dorset), from the 

 Building-Stone. It is most likely from the top layer, and so it 

 may be of the date of the -post-discitoi hemera. 



Note. — Oppelia preradiata, Douville, 1 is not a Bradfordia, 

 though there is much likeness to Br. inelusa ; for Douville describes 

 the ribs of his species as being slightly turned forwards, and ending 

 abruptly on the edge of the periphery. These are not characters 

 of Bradfordia : and in Br. inelusa especially the ribs meet about 

 the central line of the periphery, but they are alternate, not opposite. 



Bradfordia etheridgii (S. Buckman). 



1882. Haploceras etheridgii, S. Buckman, ' New Species of Ammonites ' Proc. 

 Dorset N. H. & Ant. F.-C. vol. iv, p. 143 ; (Ecotraustes (misprinted 

 Occotranstes), pi. iii, fig. 3. 



lire marks. — This species may be regarded as a Bradfordia, 

 It has the umbilical rim and general appearance of the other 

 species ; but its whorls are stouter and more involute. 



Localities and strata. — Bradford Abbas (Dorset), from the 

 Fossil Bed, and presumably the upper part. Dundry (Somerset), 

 apparently, by matrix, from the Limestone and Marl beds. 



D a t e. — -Presumably discitce hemera. 



Genus (Ecotraustes, Waagen. 

 (Ecotraustes spiniger, sp. nov. (PI. XI, fig. 7.) 



Descriptio n. — A much compressed, rather widely umbilicate, 

 and almost smooth Oppelid, with a flatfish uncarinate periphery. 

 The only ornament is some obscure falcate parvicostae, and on each 

 edge of the periphery, for a part of the outer whorl ? a row of small 

 tubercles. The mouth-border shows the base of a lateral linguiform 

 projection. 



Distinction. — This species is something like (Ecotraustes 

 serriger (Waagen) 2 ; but is thinner, with a narrower and more 

 definite periphery, has a large umbilicus, and a different arrange- 

 ment of tubercles. Our species has a superficial resemblance to 

 some of the Bonarellice of the Oxfordian ; but the ribbing is 

 different. 



This species has much likeness to Oppelia echizenica, Yokoyama 3 ; 

 but that has larger and more distant peripheral tubercles, possesses 

 a keel, and a different whorl-section. And as it is very different in 

 date, being Oxfordian or post-Oxfordian, the resemblance probably is 

 only accidental. 



1 Bull. Soc. Geoi. France, ser. 3, vol. xiii (1884-85) p. 33. 



2 'Die Formenreihe des Amm. subradiaius* Geogn. Pal. Beitr. vol. ii, pt. ii 

 (18G9) p. 230 & pi. xx, fig. 8. His fig. 7 appears to be quite another species. 



3 Journ. Coll. Sci. Tokyo, vol. xix (1904) art. 20 : p. 8 & pi. i, fig. 7. 



