A. II. Foord — Western Australian Fossils. 99 



upon this genus are those of C. D. Walcott, 1 who remarks that 

 " the genera Conularia, Hi/olithellus, Coleoprion, Coleolns, Hemiceras, 

 Salterella, I'terotheca, Phraginotheca, Matthevia, and perhaps 

 Palcenigma, form a group that, although representative, in a measure, 

 of the recent Pteropoda, differ in other respects so much that it 

 appears as though a division of the Gasteropoda equivalent to the 

 Pteropoda might be consistently made to receive them." Walcott 

 constitutes a Family — Salterellidae — for the reception of Salterella; 

 the rest of the families belonging to this Palaeozoic group being 

 Hyolithellidse, Tentaculidae, Conularidse (Salterellidae), Matthevidae, 

 and Pterothecidae. 



Describing the genus Salterella, Walcott remarks that " the shells 

 of the species of this genus are strong and comparatively thick, much 

 more like those of Tentaculites than Serpulites," and he adds, " I am 

 inclined to agree with M. Barrande 2 that the relations of the genus 

 are with Tentaculites and Hyolites " 



The species of Salterella found in Canada are from the Middle 

 Cambrian (Georgia Group, of Walcott :i ) ; the British species, Salterella 

 (Serpulites) Maccullochii, Salter, is found in the Durness Limestone 

 of Sutherland shire, a somewhat higher horizon. 



Locality. — Kimberley District. 



CRUSTACEA. 



PCECILOPODA. 



Olenellus ? Forresti (Etheridge, jun., sp., MS.), n.sp. PL IV. 



Figs. 2, 2a, 2b. 



The specimen representing this species consists only of that part 

 of the head which is contained within the free cheeks. The general 

 outline of the head was probably semicircular and rather strongly 

 convex ; it was bordered by a narrow, rounded rim, only the front 

 part of which is preserved, as seen in the figure. The glabella, 

 which is somewhat damaged, is of an elongate conical form, widening 

 gradually from the posterior to the anterior extremity ; the front of 

 it almost touching the marginal rim. Four pairs of glabella furrows 

 are present, the front pair very faintly marked. The eyes are 

 elongate, narrow, and extend in a broad arch from opposite the 

 front or anterior glabellar lobe to the occipital furrow. The space 

 between the eye-lobes and the glabella is slightly elevated. The 

 occipital segment is apparently destitute of a spine. 



On the weathered surface of a similar limestone rock, and from the 

 same locality as the head just described, there is a short spine (Fig. 

 2a) probably belonging to the present species ; if so, it would be 

 the telson. In another piece of limestone similar to those containing 

 the head and telson there is a portion of athoi'acic segment (Fig. 2b), 

 which agrees in form with the first two segments of an Olenellus ; 

 this may also belong to the present species. 



1 Second Contribution to the Studies on the Cambrian Faunas of North America, 

 Bull. United States Geol. Surv. No. 30, 1886, pp. 131, 143. 



2 Syst. Sil. de la Boheme, 1867, vol. iii. p. 138. 



3 Second Contribution on the Cambrian Faunas of N. America, Bull. U.S. Geol. 

 Surv. No. 30, 1886, pp. 20-24. 



