332 



that they and the specimens collected by Mr. Richardson, are probably 

 distinct from Morton's Ammonceratites Conradi, and it now seems desirable 

 to distinguish the former by a different and new specific name. 



The general contour and mode of coiling of H. elongatum seem to be 

 essentially similar to those of Heteroceras polyplocum, Schluter. which is 

 the type of Hyatt's recently proposed genus Bostrychoceras. 



Mr. Harvey writes that helms collected many specimens of this species 

 on the Puntledge, or Comox River, near Comox, V. I., a previously 

 unrecorded locality for it. 



Heteroceras Hornbyense, Whiteaves. 



Plate 42, figs. 1, 2, 3 and 4. 

 Heteroceras Hornbyense, Whiteaves. IhQS. Canad. Rec. of Sc, vol. vi, p. 316. 

 Heteroceras perversum, Whiteaves. 1895. Idem, p. ■'IZ. Sinistral variety. 



Original descriptions : 



II. Hornbyense. " Shell dextral, depressed turbinate, much broader 

 than high, and composed, so far as is known, of five or six rounded, ven- 

 tricose volutions, which are in close contact but without embracing ; spire 

 moderately elevated ; umbilicus broad and deep, exposing the whole of 

 the inner volutions. 



" Surface marked with simple and not very flexuous transverse ribs. 

 Upon the last volution one or two continuous ribs without tubercles 

 alternate with a rib or pair of ribs whicli bears, or bear, a small but 

 rather prominent tubercle on each side of the periphery. Usually two 

 ribs coalesce, both above and below, at each tubercle, but occasionally a 

 single thickened rib bears a pair of tubercles. In places, also, where 

 the test is preserved, the surface is seen to be marked with fine raised 

 lines, parallel to the ribs. Sutural line unknown. 



" Maximum breadth of the outer volution of the largest specimen col- 

 lected, nearly two inches and three-quarters. 



" Hornby Island, W. Harvey, 1894 ; two specimens, one with most of 

 three volutions, and the other with the whole of four volutions and a 

 part of the fifth preserved." 



H.jyerversnm. " Shell sinistral, but in other respects essentially similar 

 to that of the preceding species. 



"Hornby Island, W. Harvey, 1894 ; a single specimen about an inch 

 and three-quarters in its maximum diameter, with nearly the whole of 

 one volution remarkably well preserved. 



