174 CADULUS-GADILA. 



the shell at the anal opening is not thickened, and both ends are 

 narrower. Than Cadulus gracilis JefFr., this is much smaller, more 

 attenuated, has a gibbous swelling, and not a mere equable enlarge- 

 ment, and has both openings much smaller. 



From Cadulus jejfreysi Monter., it differs still more strongly in 

 these very respects, except that in size it is nearer. 



C. AMIANTUS Dall. PI. 25, fig. 52. 



This species, first identified by me with C. sauridens Watson, was 

 submitted to Mr. Watson for examination. He writes : " Compared 

 with C. sauridens it is three times as long, mouth not oblique nor 

 regular; form much more bent, swelling much more pronounced 

 and nearer the anterior end. The transverse contour line is more 

 circular, there being little if any flattening between the convex and 

 concave slopes. It is more like C. vulpidens Watson, but is only 

 half the length of that species, and less conical behind the ' equa- 

 tor/ and more conical in front of it. The equator is less angulated 

 than in C. vulpidens, and not so near the mouth." The length of 

 C. amiantus is 5'75, its maximum diameter 1-4 mill. Both orifices 

 are circular and not notched, and the swelling evenly shades off 

 toward the extremities. The specimens obtained off Cape Florida 

 are more slender than the typical form. (Dall). 



Off Cape San Antonio, Cuba, in 1,002 fras. (Blake); off Cape 

 Florida, in 8 fms. (Dr. W. H. Rush). 



Cadulus sauridens DALL, Bull. M. C. Z., ix, p. 36 (1881) ; not of 

 Watson, 1879. Cadulus amiantus DALL, Bull. M. C. Z., xviii, 

 Blake Rep., p. 431, pi. 27, f. 7. 



C. BASTRIDENS Watson. PI. 25, fig. 62. 



Shell like the tooth of a rake, small, narrow, bent, swollen, and 

 on the convex curve very faintly angulated at about five-eighths of 

 its length, from which point both the bend and the narrowing of 

 the shell is greater (proportionally) toward the mouth than it is 

 toward the apex. Between the back and the belly there is a very 

 slight compression of the shell. It is pretty strong, brilliant, more 

 or less obscurely banded transversely with alternate equal threads 

 of opaque and transparent white. Sculpture : Very faint, superfi- 

 cial, transverse scratches. Mouth pretty large, not at all oblique, 

 thin, sharp and chipped ; posterior opening round, straight ; edge 

 thickened, and less chipped than the mouth. Length 0'119 inch, 



