12 University of Michigan 



but the outer rows are usually more constant throughout their 

 lengths. The body of each of these teeth is attenuate anteriad, 

 so that the base is narrow. The cusps of each tooth are more 

 nearly equal in size than in D. dominiciis. Each half of the 

 transverse rows is quite straight and extends obliquely anteriad 

 from the center. 



For comparison, the radulae from two specimens of Dry- 

 imvus nuiltiUncatus^ were examined. The rhachidian tooth is 

 stout and short; the symmetrical tip is markedly recurved and 

 bears three cusps. Most of the lateral teeth bear 4 cusps, but 

 a reduction to 3 very commonly occurs in some of the inner 

 three longitudinal rows. The enlargement of the second cusp 

 from the inside, on each tooth, is even more noticeable than in 

 D. dominicus. The body is attenuate anteriad somewhat as in 

 D. albosfyiafus. The transverse rows are V-shaped; each half 

 extends obliquely anteriad from the center for a short distance 

 and then curves slightly outward. The radular formula is 

 144—1—144- 



Oxystyla princcps (Sowerby). Twenty-two adult or nearly 

 adult and i juvenile specimens ; mainly from trees in the 

 thick jungles (H, i, b), but also from the partially cleared 

 places along Arroyo Hueyapam (H, ii, a) and the savannah 

 brush (H, iii, b). Dead shells also picked up from the ground 

 in the jungle (H, i, a) and the burnt-over places (H, ii, b). 

 This species appears to be purely arboreal, and I have found it 

 aestivating in cavities in the trees. 



These specimens are very variable in color and pattern, but 

 no relations between these characters and the habitat could be 

 made out. The variation may be analyzed as follows : 



lA. N. S. P. No. 88,779; Sugar Loaf Key, Fla. ; J. B. Clark, May 

 23, 1921. 



