166 



It is with, much pleasure I associate with the species the 

 name of the proprietor of the land on which the chief fos- 

 siliferous deposits of Muddy Creek are found ; also because of 

 his hospitality and assistance rendered to all visitors in search 

 of fossils. 



Tellina aequilatera, spec.nov. Plate xvi., figs. 5a — 5b and 9a— 9& ; 

 plate xx., fig. 19. 



Ovate-oblong, subequilateral, rather thick, smooth, and 

 somewhat convex. Post-dorsal margin straight, a little more 

 descending than in front, which is slightly incurved ; front 

 margin broadly rounded ; posterior side narrower, abruptly 

 and narrowly rounded at the extremity. There is a slight 

 radial depression near the post-dorsal margin, proceeding from 

 the umbo, which produces an inconspicuous insinuation at the 

 posterior extremity. The umbones are small, acute, and situated 

 a very little in front of the centre. 



The exterior is ornamented with fine incised concentric lines 

 and zones of colour. The siphonal inflection is very deep, 

 narrow, rounded at the extremity, reaching to near the anterior 

 adductor scar, and is quite detached from the pallial impres- 

 sion. 



The left valve has one bifid cardinal tooth ; the right valve 

 with two cardinal teeth, the posterior one much larger and 

 bifid ; a strong lateral tooth on each side, the anterior one 

 being nearer to the cardinal teeth. 



Dimensions of a medium-sized example : — Antero-posterior 

 diameter, 52 ; umbo-ventral diameter, 35 ; sectional diameter 

 of left valve at three-sevenths from the umbo, 8 - 5 millimetres. 



Locality. — Upper beds at Muddy Creek ; calciferous sand- 

 stone, Eiver Murray Cliffs, near Morgan. 



Plate xx., fig. 19, represents an adult example from Muddy 

 Creek ; plate xvi., fig. 5, an averaged-size specimen, also from 

 Muddy Creek ; plate xvi., fig. 9, is a young shell from the 

 Piver Murray Cliffs — the figure, however, is not correct, being 

 too much angled posteriorly, and too much arched ventrally. 



Tellina Stirlingi, spec. nov. Plate xvi., figs, la — lb. 



Elongate-oval, considerably inequilateral, rather thin, sub- 

 pellucid, and somewhat convex ; the anterior side is half as 

 long again as the posterior, narrowed and subacuminately 

 rounded behind. Surface ornamented concentrically with 

 slender, not crowded, subacute ridges, and a few broadish fur- 

 rows. 



There are two cardinal teeth in each valve, and well- 

 developed laterals in the right. The siphonal sinus is large, 

 rounded, ascending into the umbonal cavity, reaching to mid- 



