4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 9I 



rounded, marked by heavy humplike axial ribs which attain their 

 greatest development on the anterior two-thirds of the whorls. Of 

 these ribs, which are about twice as wide as the spaces that separate 

 them, 8 occur upon the first and second, 9 upon the third, 10 upon 

 the fourth, 12 upon the fifth, and 9 upon the last whorl. In addition, 

 the entire surface of the shell is marked by fine incremental lines. 

 The spiral sculpture consists of heavy spiral cords, which cross the 

 axial ribs. Of these cords, two occur upon the first three postnuclear 

 whorls which are separated by spaces equal to them in width, while 

 three are present on the fourth. Of these, the first is a little less strong 

 than the other two. On the fifth whorl four of the strong cords are 

 present, of which the third is a little less strong than the other three, 

 which are about equal. The last whorl has five of these strong cords, 

 of which the third and fifth are not quite as strong as the others. In 

 addition to these, there are two moderately strong cords at the ap- 

 pressed summit of all the whorls but the first, which has one. In 

 addition to the heavy spiral sculpture there is a secondary and much 

 weaker sculpture which consists of fine spiral lirations. Of these 

 there are three present on the first postnuclear whorl between the 

 cord at the summit and the two strong cords anterior to the sinus. On 

 the second whorl between the two moderate cords at the summit and 

 the two strong cords anterior to the sinus, the sinal region is marked 

 by six lirations, while three are present between the two strong cords. 

 On the third whorl 1 1 lirations occur between the cords at the summit 

 and the first strong cord anterior to the sinus, and 5 between the 

 two strong cords. Between the two moderate cords at the summit 

 of the fourth whorl one spiral liration is present, while nine occur 

 between the moderate cords and the first strong cord, three between 

 the first and second strong cords, and eight between the second and 

 third. The fifth whorl is marked by 2 spiral lirations between the two 

 cords at the summit, 14 lirations from the second cord at the sum- 

 mit and the first strong cord, 6 between the first and second strong 

 cords, 2 between the second and third, and 5 between the third and 

 fourth. There are nine lirations between the fourth cord and the 

 suture. The last whorl, like the fifth, has two spiral lirations between 

 the cords at the summit. The sinal region is marked by 16 spiral lira- 

 tions while the spaces between the 5 strong cords anterior to the sinus 

 are marked by 5 lirations between the first and second, 2 between 

 the second and third, 5 between the third and fourth, and 2 between 

 the fourth and fifth. The combination of the fine spiral lirations and 

 the incremental lines produces a clothlike pattern, and the junction 

 of these two fine elements gives to the shell a finely granulose aspect. 



