309 



Length of a large specimen 3 J inches ; width 3 inches. 



Locality and Formation. Point Levis ; limestone of the Quebec group. 



Collectors. -T. Devine, Esq., T. C. Weston. 



HELICOTOMA MISER. (N. sp.) 

 H. perstriata. Q-eol. Can. pp. 233, 862. 



Description. Shell small, with four slender, but strongly carinated 

 whorls. Spire flat, the whorls on the upper side, with two strong, acutely 

 angular carinse of equal height, separated by a deep, concave groove, 

 which is visible quite to the apex. The inner carina is situated a little 

 more than one-third of the width of the whorl from the suture. The 

 outer carina rises vertically from the periphery. From the inner carina, 

 there is a flat slope, extending down to the bottom of the deeply excavated 

 suture at an angle of 45 p . From the edge of the outer carina there is a 

 vertical descent, one-fourth the depth of the whorl, forming a flat band at 

 a right angle to the plane of the spire. This band is bounded on its lower 

 side, by an angular carina, the upper side of which forms an abrupt 

 projection at a right angle to the band. Below this carina, the whorl 

 appears to be vertical, or nearly so for one-fourth its depth, and then 

 rounded into the umbilicus, this lower rounded part being ornamented by 

 fine sharp striae following the whorls. No striae across the whorls are 

 visible on this specimen, but, no doubt, they exist. 



Diameter 6 lines ; width of the last whorl at the aperture If lines ; 

 depth about, the same. The umbilicus is not visible in the specimen, but 

 it is probably about one third the whole diameter. 



Only one specimen has been seen, and this is perfect above, but has its 

 base imbedded in the matrix. 



I have heretofore referred this species to H. perstriata of the Calciferous 

 formation, but now think it may be separated as a closely allied species. 

 In that species the inner whorls of the spire are a little elevated above 

 the outer ; and the concave groove between the two carinae on the upper 

 side of the whorls, as well as the slope into the suture, are longitudinally 

 striated. The band below the outer carina is not quite vertical, one third 

 the depth of the whorl, longtitudinally striated and obscurely divided into 

 two bands by an elevated line along the middle. None of these characters 

 are possessed by H. miser. 



Locality and Formation. Point Levis ; in limestone No. 2, Quebec 

 group. 



