164 RECORDS OF THE AUSTRALIAN MUSEUM. 



The arrangement of the tubercles in three rows on each side the 

 median line of the venter, and but two here, would in the 

 ordinary course separate the two portions, but in many Crioceri 

 the number of rows varies on different portions of the shells. 

 There is, on this account, the bare possibility of the shaft now 

 under description being that of C. lampros. Of the three speci- 

 mens this also exhibits the truncate outline of the venter in a 

 more marked degree than in the other two, although it is quite 

 apparent there also. 



Again, the hexagonal section around the primary costa?, the 

 simplicity of the latter, and their markedly straight course and 

 trenchant nature of the venter, with the additional line of 

 tubercles on each side, will serve to distinguish this limb and 

 crozier from those of G Jlindersi, McCoy. 



The second is a crozier and part of a shaft on which the 

 primary cost* are more regularly spaced apart. 



Tn the third specimen, provisionally united with the first and 

 second, the proximal end of the limb is preserved (PI. xlvi., fig.2); 

 this does not lead to a coil, but is returned on itself in the form 

 of a hook after the manner of D'Orbigny's Hamites. The con- 

 tiguity of the two portions is so close there could by no possible 

 means have been room for a coil ; the deduction is therefore 

 reasonable that we are here dealing with a specimen possessing 

 geuerally the appearance of such a shell as Hamites eleoans, 

 D'Orb., nor does there appear to have been space for a second 

 return of the limb as in //. attenuatus, J. Sby., the type of 

 Hyatt's genus TomeutocerasA !l On the whole, this form does 

 not appear to be a Crioceras pure and simple, nor can it be 

 included in the Hamitid* of Hyatt's classification, one of the 

 characters of the latter being "no tubercles at any stage." 



Locs. — Tambo, Barcoo River, Central Queensland (Plate xlii., 

 fig. 1) [A.M. (Mrs. Alice Hamilton)]. Barcoo, Ward and Nive 

 Rivers District (PI. xlvi, fig. 2; PI. xlvii., fig. 5) [A.M. (//. W. 

 Blomjietd)]. (?)Central Australia [G.S.]. 



Genus Leptoceras, Uhlig, 1883. 



(Denksch. K. Akad. Wissensch. Wien., xlvi., 2, 1S83, p. 260.) 



Obs. — Mr. V. Uhlig established Leptoceras as a subgenus of 

 Crioceras for dwarfed forms with an open coil and the first or 

 first and a half whorls noncostate, and the sutural divisions with 

 tew ramitications ; he cited as examples of his subgenus C. /mzo- 

 sianum, D'Orb., and G.cristatum, D'Orb. The costai are straight 

 and slightly inclined towards the front. Uhlig remarks that the 



'• Hyatt -Zittel's Text-Book Pal., Eastman's Edition, i., 1900, p. 586. 



