LOWER CRETACEOUS FOSSILS — ETHERIDGE. 157 



Another very interesting point in connection with this species 

 is the occurrence in the Port Darwin beds of shaft portions 38 

 reproducing in every particular, in miniature, the features of the 

 flat-ventered variety of C. flindersi just referred to. I am at 

 present at a loss to account for these miniature forms at Point 

 Charles, unless they represent a dwarfed race of species found in 

 other portions of the Australian Cretaceous. 



Loc. — Whitewood Ridge, Sesbania, North-Central Queensland 

 [G.S.Q.]. Cameron Downs, south of Hughenden, North Queens- 

 land [G.S.Q.]. Flinders Piver, Carpentaria [Q.M.] Saltern 

 Creek, north of Barealdine, Central Queensland [Q.M.J. Well- 

 shot Run, near Barealdine, Central Queensland [Gr.S.Q. Mount 

 Cornish, near Muttaburra, Central Queensland [Q.M.]. Barcoo, 

 Ward and Nive Rivers District [A.M. (//. IV. Blomfield)]. Head 

 of Flinders River, North Queensland [N.M.M. (Messrs. Cay-son 

 and Sutherland; McCoy's type)]. Olive Downs, near Milparinka, 

 North-west New South Wales [M.G.M.] Charlotte Waters, 

 Central Australia [N.M.M. , G.S.S.A.]. Dalhousie Springs, north 

 of Oodnadatta, Central Australia [G.S.S.A.j. Central Australia 

 [G.S.]. 



Ckioceras lampros, 38 " sp. nov. 



(Plate xlviii.) 



Sp. Chars. — Shell ponderous, attaining a diameter of twenty- 

 one inches at least, but only one and a quarter whorls are known. 

 Venter generally truncate; abdominal lines indicated by a row 

 of tubercles on each side the middle line of the venter; dorsum 

 flat, costate, very broad at the distil end ; impressed zone 

 obliterated; flanks flattened, broad; section generally quadrate, 

 becoming distinctly octagonal on the fully tuberculated costse. 

 Sculpture consisting of costaeof two kinds, primary and secondary; 

 the former on the venter and flanks are large upstandirg crests 

 at regular intervals apart, and tubercle-bearing, but on the 

 dorsum are not to be distinguished from the secondary cost* 

 occupying the intercostal spaces ; on the venter the costa? are 

 straight (transverse), straight or very slightly curved on the 

 Hanks, and on the dorsum convex forwards. Tubercles very large 

 and strong, in three rows on each side, one abdominal, one infra- 

 abdominal, and the third supra-umbilical (or supra-dorsal). 



Obs. — This form is known to me only as two almost completely 

 exfoliated whorls of large size, and a few disjointed pieces. It 



3 «Etheridge— Ibid, 1907 (Suppl. No. 55, 1906), p. 16, pi. x., tigs. 6-0. 

 3 sa An/n7rpos, magnificent. 



