54 University of Michigan 



sides as around the umbilicus ; it breaks the growth sculpture 

 into elliptical bosses, or even produces a cancellate appearance. 

 Earlier whorls : markedly cancellate, with cusp-like bosses at 

 the intersections. Umbilicus : a trifle larger than in muskusi. 

 Peristomal callus : thinner than in muskusi. Other characters 

 as in muskusi. 



Measurements 



C14. Very common (311 specimens collected). Tj^ical lot (see Table 

 V) ; includes many specimens with fine, rather closely-spaced growth- 

 costae, cut by poorly-developed spiral sculpture. 



C15. Very rare. Amongst the large numbers of shells examined in the 

 field, 6 beautifully cancellate specimens were separated as quite character- 

 istic of grandien-sis. One other shell gives the appearance of a hybrid 

 between T. fossor djcrimcnsis and T. muskusi; a similar specimen comes 

 from C17a (fig. xii-H). 



This subspecies intergrades with the more southern forms 

 of muskusi, but not with the typical form. 



Tudora muskusi bullenensis, new subspecies 



Type locality: (C13) top of Seroe Largoe, just southwest of 

 entrance to Salinja Sint Marie, near Sint Willebrordus, north- 

 ern Curacao. 



Distribution : only collected from the top of this hill ; it was 

 not found at the base of the escarpments, or on the hill east 

 of the entrance to the salinja. Infrequent, on trees and brush 

 and under rocks. 54 specimens collected. 



Shell (fig. xii-G) : thinner and more slender than grandi- 

 ensis. Ground color: bleached; whitish to pinkish; spiral 

 bands absent, except for a very faint umbilical band in a few 

 specimens ; eroded apex and apical plug yellowish, pinkish or 

 purplish-drab; dilute varices of these last colors also common. 



