LAMP AS. 41 



that the balance of characters will agree best with its position 

 in the present genus. I cannot doubt that R. coriacea, Reeve 

 (fig. 20), is a juvenile state of the same species. 



R. PUSTULOSA, Reeve. PL 22, fig. 33. 



Shell ponderous, chestnut-colored, with two or three rows of 

 chocolate-colored, distant, rounded tubercles ; margins of aperture 

 orange-brown. Length, 1/5 to 2'25 inches. 



Ascension Isl., Atlantic 0., 280 m. N. W. of St. Helena. 



Larger and more ponderous than R. caelata, with larger and 

 less numerous tubercles ; the latter, however, are more numerous 

 on the earlier whorls, and it would probably be difficult to dis- 

 tinguish a young specimen from R. caslata. The great difference 

 in the habitat of the two species may readily account for their 

 distinctive features, supposing, as is probable, that they were 

 originally derived from a common stock. 



R. C^LATA, Brod. PI. 22, fig, 34. 



Shell dark chestnut-color, with a number of dark chocolate 

 colored tubercles, arranged in several rows. 



Length, 1 to 1/75 inches. 



Panama. 

 R. CANDTSATA, Lamarck. PL 22, fig. 43. 



Yellowish white, maculate with brown. Length, 4 to 5 inches 



Philippines, Isle of Annaa. 



Distinguished from the following forms by its large size and 

 elongated spire, 



R. GRANIFERA, Lam. PL 22, figs. 35-37. 



Shell with high spire, rather thin. Light yellowish brown, 

 stained and maculated with a darker tint, sometimes obscurely 

 white banded, tubercles white ; white within. 



Length, 1*5 to 2-25 inches. 



Red Sea, Natal, Paumotus, Philippines, N. E. coast of Australia. 



R. semigra/nosa, Lam., (fig. 37), is a state of this species in 

 which the granules are obsolete. I separate R. affinis, Brod. 

 (with its synonyms), from this species only with great doubt, for 

 although that species is normally more ventricose, with larger 

 tubercles, replacing the granules in one to three rows, yet there 

 are intermediate forms which it is difficult to place. 



