114 



a 



lines, generally much more distinct in the furrows than on the ribs between them, and more 

 or less marked on the anterior alations ; a few stronger wrinkles of growth are also usually 

 seen at more distant intervals, especially near the lower margins of the valves, where they are 



more crowded together, 

 ft and present a zig-zag ap- 

 pearance in crossing the 

 costse and furrows. Length 

 of a mature, rather short, 

 gibbous specimen, from the 

 anterior basal angle to the 



vj.\\\'-.''i '.'?^J posterior extremity of the 



hinge, 1.32 inches; from 

 beak to same, 0.65 inches ; 

 Flo 50 height of top of umbones, 



Conocardium trigonale (Hall); a. Side view of a medium sized, mature speci- v-72 inches ; convexity of 

 men, being mainly an internal cast, with the umbonal alations and the anterior beak- the tWO valves anteriorly, 

 like appendage broken away ; b. View of the underside of another specimen, retain- /% QJ ; V, /AT 1 T> 1 

 jng a portion of the alation (al), which extended at least as far forward as indicated v.\)' inCD. (iVleeK, _rai830n- 

 b y the dotted line. (After Meek). tology of Ohio, p. 201). 



Specimens of Conocardium trigonale appear to be common in parts of the Corniferous 

 Limestone, but, so far, I have only met with exceeding fragmentary and broken specimens, 

 though these can readily be recognised by their surface characters, and by the singular ala- 

 tions produced from the margins of the truncated anterior side. I have, therefore, contented 

 myself with simply reproducing Meek's full description and a portion of his figures of this 

 species. If Pleurorhynchus trigonalis (Phillips), be a valid species, and not identical with 

 Conocardium Hibernicum (Sowerby), then the use of the specific name trigonalis, for the Ame- 

 rican form must be a abandoned, and D'Orbigny's designation of sub-trigonale will have to be 

 adopted. 



Locality and Formation. Corniferous Limestone of Hagersville, Township of Oneida. 



PTEROPODA. 

 137. TENTACULITES sp. 



Under this head, I can simply note the occurrence in great abundance in the Hamilton 

 group of a species of Tentaculites, which is probably not new, but which I am unable to 

 identify with any species previously described, in consequence of my not having access to all 

 the published descriptions of these fossils. In almost all respects it agrees with Tentaculites 

 annulatus (Schlotheim) ( = T. scalaris ibid), but the latter is described as having the surface 

 covered with very minute longitudinal striae, no such structures being visible in the former. On 

 the contrary our species agrees with Tentaculites ornatus (Sowerby). in having the interspaces 

 between the regular annulations ringed with from three to seven fine sharp encircling striae. 

 It is, however, apparently not identical with T. ornatus, as it seems to be a longer form, and 

 to have the annulations more closely set. In the absence, however, of authentic specimens of 

 either T. annulatus or T. ornatus, I can simply leave the specific determination of the Canadian 

 form an open question. 



Locality and Formation. Very abundant in the Hamilton Formation, Arkona, Township 

 of Bosanquet. 



GASTEROPODA. 



The! number of Gasteropoda in the Devonian Rocks of Western Canada is very consider- 

 able, and this is especially the case as regards the Corniferous Limestone. By far the majority 

 of specimens, however, occur in the state of casts, with little or none of the original surface 

 preserved, often crushed, or mutilated in different ways; and it is thus often impossible to 

 determine their true affinities or to decide with certainly to what species they may belong. I 

 have thus been compelled to leave altogether unnoticed a number of univalves of which noth- 

 ing definite can be made with the materials at present in my hands ; whilst the determination 

 of these here recorded must be regarded as more or less doubtful and provisional. The only 

 Gasteropod which has come under my notice from the Hamilton group is a Platyceras, and 



