clxxii INFERIOR OOLITE AMMONITES. 



From Dumortieria radians, stouter whorls, a flatter periphery, a less definite 

 carina. 



Remarks. — The absence of the paucicostate stage (the evidence is furnished by 

 other specimens), which is so noticeable in Dumortieria, even when more degenerate 

 than this species, and the association of spissicostation with quadrate whorls and an 

 open umbilicus, suggest that the generic position is Catulloceras. 



Localities and Stratum. — Dorset : neighbourhood of Bradford Abbas, Yeovil 

 Sands. Somerset : Furzey Knaps, near Yeovil, in the same beds, associated with 

 several new allied species. 



In the following species the periphery shows more or less definite furrows 

 beside the carina. Place here also Ammonites Perroudi, Dumortier et Fontannes, 

 and Cat nil. a.ratum, S. Buckm. 



3. Catulloceras stjbarattjm, Brasil. Plate XXXIX, figs. 1, 2. 



1891. Dumortieria arata, This Monogr., PI. xxxix, figs. 1, 2. 



1892. Catulloceras aratum, This Monogr., p. 280 (pars). 



1895. Catulloceras subaratum, Brasil, Ceph. nouv., Bull. Soc. Geol. Normaiulie, 



vol. xvi, PI. iv, figs. 1, 2. 



Remarks. — Dr. L. Brasil has found this species in Normandy, and has rightly 

 corrected me by separating this from the compressed form under a distinct name. 



III. Genus — Dumortieria, Haug. 



1891. Dumortieria, This Monogr., p. 231. 



Rectiradiate. 

 Paucicostate. 



1. Dumortieria prisga, S. Buchman. Plate XXXVII, figs. 9 — 11. 



1891. Dumortieria prisca, This Monogr., PI. xxxvii, figs. 9 — 11, p. 230. 



Localities ami Strata. — Somerset: Hendford Hill, Yeovil, in "the Sands." 

 Gloucestershire : Penn Wood, Cephalopoda Bed, middle (" Dumortieria Beds"). 

 This specimen, 08 mm. in diameter, has last whorl sparsicostate to smooth, failure 

 of costation beginning about 55 mm. in diameter. 



Vale <</' l'!,rislrncr. Dumortier ise. 



