168 MICROCERAMUS. 



Eastern Cuba: at the mouth of the Yateras river (Jean- 

 neret) . 



Macroceramus simplex PFR., Malak. BL, xi, 1863, p. 19; 

 Novit. Conch., p. 407, pi. 93, f. 30-32; Monogr., vi, 350. 

 ARANGO, Fauna, p. 84. 



I have not seen this species, which according to Pfeiffer is 

 related to M. turricula (petitianus). It may be a Macro- 

 ceramus. 



Group of M. costellaris. 



Imperforate or nearly so, acutely conic, opaque whitish, 

 usually marked with a series of spots above the periphery 

 and suture. Suture not noticeably denticulate, the riblets 

 not beaded above it. Columellar margin dilated above and 

 usually adherent, not built forward from the columella 

 proper. Apical whorls costellate and usually black. All 

 known species are from Pinar del Rio. 



I. Apical whorls black; imperf orate. 



a. Periphery rounded; rather strongly rib-striate 

 throughout; whitish, lusterless, with a series of 

 irregular spots above the periphery. 



M. costellaris, no. 16. 



b. Periphery rounded; very finely striate, almost 

 smooth. M. paivanus, no. 17. 



c. Periphery angular; smooth, becoming striate on the 

 spire; glossy white, with a band of oblong spots 

 above periphery. M. nigropictus, no. 18. 



II. Apical whorls corneous. 



a. Subperforate, trochiform, corneous irregularly mac- 

 ulate with white (or gray-white, irregularly marked 

 with brown) ; last whorl rather acutely carinate. 



M. maculatus, no. 19. 



b. Perforate, widely ovate-conic, whitish variegated 

 with corneous and with a corneous band (or series 

 of spots) ; last whorl rounded or but faintly sub- 

 angular. M. latus, no. 20. 



