\ 



20 



Chonetes Laticosta. (Hall.) 



Chonetes Laticosta (Hall). Tenth N. Y. Rey. Reb.p. 119, 1857 Pal. N. Y. vol. IV, p. 



125, 1867. 



Description. — Shell small, semi-elliptical ; width about one-fourth greater 

 than the length ; cardinal angles about 90*^, sometimes a little less ; sides 

 straight or gently concave for about one-third their length from the angles 

 forwards ; anterior half of the shell uniformly rounded. The ventral 

 valve is usually strongly convex, most elevated at about the posterior 

 third of the length, the umbo broad and rounded, the cardinal angles 

 somewhat^ flattened or concave. The area is narrow, and appears to be 

 nearly in the plane of the lateral margins. Surface with from eighteen to 

 twenty-five strong, rounded or sub-angular radiating ribs, which are either 

 single throughout the length of the shell, or, occasionally, sub-divided 

 about the mid-length or a little in front thereof. The largest specimen 

 in the collection is about six lines in width on the hinge line, and five lines 

 in length. The others are about five lines wide. The dorsal valve has 

 not been seen. No spines or indications thereof are visible. 



This species differ^ scarcely at all from that of the Corniferous lime- 

 stone, which Prof. Hall has described under the abo7e name. The few 

 specimens from the Corniferous that have been compared have the ribs 

 somewhat smaller, but in no other respect is there any difference of impor- 

 tance. Prof. Hall intimates that C, laticosta is somewhat variable in 

 its characters. 



Locality and Forynation. — At Little Gaspe, Grand Greve and Indian 

 Cove, Gasp^. In the Gaspe limestone. No. 8. 

 Collectors. — Sir W. E. Logan and R. Bell. 



Strophomena Galatea. (N. sp.) 



Fig. 9. 



Fig. 9. — Sirophomena Galatea. External view of a ventral valve, partly restored. 



Description. — Shell of a medium size, semi-elliptical ; cardinal angles 

 about 90^ ; sides in the posterior half nearly straight and parallel ; all of 

 the exterior half uniformly rounded. Ventral valve exceedingly convex 



