from Western Australia. 391 



present species. Both have been recorded from Western Australia. 

 Ammonites Moorei, Lycett,^ differs both as regards sculpture and the 

 form of the suture-line ; in fact it belongs to Bumortieria. As we 

 have already remarked, the present species is most probably the 

 same as that which Moore figured under the name A. radians, 

 Schlotheim (Nautilus radians, Keinecke) ; a name which has been 

 given to various species of Ammonites, as Mr. Buckman^ has pointed 

 out ; the present specimen certainly does not agree with Eeinecke's 

 figure of " Nautilus radians." ^ We therefore suggest for the 

 Australian species the trivial name Glarlcei. 



According to Mr. Buck man all the species of Dorsetensia are found 

 in the Humphriesianus-zoue, with the exception of two forms, which 

 occur in the Sauzei-zone. 



Locality. — Champion Bay, Western Australia. 



Ammonites (Stephanoceras, W. Waagen). 

 Ammonites (Stephanoceras) Australe, sp. nov. (PL XII. Figs. 4a, &.) 



? 1870. Ammonites macrocephalus, C. Moore, "Australian Mesozoic Geology and 

 Palaeontology," Quart. Journ. Geol. Soc. vol. xxvi. pp. 227, 232, 

 pi. XV. f. 5. 

 Sp. char. — Shell (cast) discoidal, somewhat inflated, not very rapidly increasing ; 

 greatest thickness at about the middle of the lateral area, about two-fifths of the 

 diameter of the shell ; height (breadth) of outer whorl rather more than one-third 

 of the diameter of the shell. Number of whorls and amount of inclusion unknown ; 

 umbilicus wide, fully one-third of the diameter of the shell in width. Whorl 

 somewhat depressed, elliptical in section, a little thicker than high, slightly indented 

 by the preceding whorl ; periphery convex, a little flattened ; sides convex, inner 

 area rounded, imperfectly defined. Each whorl bears about twenty-five short 

 umbilical ribs, each of which commences at the suture, extends with a slight forward 

 inclination over the inner third of the lateral area, and terminates in a well-marked 

 radially elongated tubercle. Each tubercle gives rise to two subangular (in the cast) 

 ribs, which pass uninterruptedly over the periphery. Single ribs are occasionally 

 interpolated between the pairs. There are about sixty peripheral ribs to a whorl, and 

 on the periphery the interspaces are wider than the ribs. Suture-line unknown. 

 Length of body-chamber unknown and aperture not seen. 



Dimensions : — 



Diameter of shell 62 mm. 



"Width of umbilicus* 24— ,, 



Height of outer whorl 20 ,, 



Thickness of outer whorl f 2'^-\- , , 



* Too large, owing to distortion of specimen. 



t Probably too small, owing to crushed condition of whorl. 



Bemarhs. — This species is represented by only one example, which 

 consists of the greater part of the outer whorl, somewhat^ damaged 

 and distorted, and much obscured by the matrix on one side. The 

 mouth-border is not preserved, and there is no trace of the suture- 

 line. 



1 Lycett, The Cotteswold Hills, 1857, p. 122, pi. i. fig. 2. (The suture-line 

 represented in fig. 2« does not, according to Mr. S. S. Buckman, belong to this 

 species. Mr. Buckman gives the sutui-e-line of Lycett' s figured specimen in his 

 Inf. Ool. Amm. (Mon. Pal. Soc), pt. v. 1891, pi. xliv. f. 9.) 



2 S. S. Buckman, Inf. Ool. Amm. (Mon. Pal. Soc), pt. iv. 1890, p. 188. 

 ^ Maris protogaei Nautilos et Argonautos, etc., figs. 39, 40. 



