SUPPLEMENT.— DUMORTIERIA. clxxix 



Costa tr to Spissicostate. 



17. DUMORTIERIA RHODANICA, Haug. 



1874. Ammonites radiosus, Dumortier finni SeebacK), Depots Jurassiques, vol. iv, 



PI. xiv, figs. 3, 4 only. 



1887. DlTMORTIERIA RHODANICA, Haug, POLYMORPH., N. JallHi. f. Mineral, etc-.. 



Bd. ii, ]>. 138. 



'Remarks. — Dumortier figured two specimens under the name of Am. radiosus; 

 one he called "compressed variety," the other "the stout form." To both of these 

 Haug subsequently gave the name Dumortieria rhodanica. As Dumortier called 

 the latter the commoner form it is advisable to take it as the type. 



The combination of stout whorls with numerous costse brings this form nearest 

 to D. pseudoradiosa, but the whorls are thinner and the costee are more numerous 

 in the present species. 



Distinction. — From D. regtdaris, stouter whorls, more numerous smaller costae, 

 larger umbilicus. 



Locality and Stratum. — Gloucestershire : Venn Wood, near Stroud, in the middle 

 part of the Cephalopod Bed, where several examples have been obtained by Mr. 

 (<. Upton and myself. 



Date of Existence. — Dumortierix hemera. 



18. Dumortieria badians (Reineche). Plate XLII, figs. 8—10; woodcut, fig. 2. 



p. 187. Suppl., Plate XXII, tigs. 31—33; 

 Pig. 1 75, p. cxcvi. 

 1891. Dtjmortieria radians, This Monogr., PI. xlii, fi<>-s. 8 — 10 ; ]>. 248 (pars). 

 Description. — Sublatumbilicate ; subspissiparvicostate ; periphery subtabulate, 

 carinate. 



Remarks. — The example figured in the present Supplement, PI. XXII, figs. 

 31 — 33, has closer agreement with Peinocke's original delineation than any other 

 specimen. It will form a basis from which to work in understanding this species. 

 Localities a ml Strata. — Gloucestershire: Penn Wood, near Stroud, and Cam 

 Down, near Dursley, Cephalopod Bed, Durnortieria horizon ; Somerset : Maes 

 Knoll (Dundry) (L. Richardson), presumably from clays of hill flank. 

 Date, of Fjsistence.—Dumortierise hemera. 



10. Dumortieria siGNATA, S. Buckma/ii. Plate XLII, figs. C>, 7. Suppl., Fig. 176, 



p. cxcvi. 

 18D1. Dumortieria radians, This Monogr., PI. xlii, figs. 6, 7 only. 

 1902. Dumortieria signata, Emend. Amm. Nom., p. 6. 



Description. — Sublatumbilicate ; subplaty-subleptogyral ; spissiparviGOstate ; 

 periphery fastigate, subcarinate. 



