136 THE NAUTILUS. 



A species of peculiar form. No other Rhytidopoma (= Cteno- 

 poma, preoccupied) is of this shape. A slight approach to the 

 sculpture of R. tollini is seen in R. perspectivum. In life the 

 shells are thickly coated with soil. 



MICROCERAMUS LONGUS, N. SP. 



BY JOHN B. HENDERSON. 



Among a lot of shells recently received from a limestone hill 

 belonging to the Cubitas range in northern Camaguay Province, 

 Cuba, is a new Microceramus belonging to the gossei group but 

 quite distinct from that well-known and widely-distributed 

 species. It is figured on plate vi, fig. 4. I give the following 

 diagnosis : 



Shell imperforate, turrited, tapering above the tenth whorl 

 to an entire apex. Nuclear whorls two, ribbed. Opaque cor- 

 neous brown streaked with wide white patches. Sculptured 

 with oblique, closely pressed strire, about 50 on lower whorls. 

 Below and sometimes crossing the suture an irregularly spaced 

 row of white nodules or bosses, less frequent in upper whorls. 

 Whorls 15, well rounded in upper series becoming almost flat 

 on cylindrical portion of shell. Base shows a very faint keel. 

 Aperture slightly oblique, almost round, with white and very 

 feebly expanded lip, the converging ends separated by smooth 

 parietal wall. Axis simple. 



Length 14, diam. 3.5 mm.; length ap. 2.75 mm. 



Length 12, diam. 4 mm. 



Length 10, diam. 3.25 mm. 



In the lot received there is but little variation in color or dis- 

 position of white sutural nodules, but some range in size. The 

 large number of whorls and the general facies of the shell at 

 once suggests the Spiroceramus group, but the absence of an 

 axial lamella precludes it. 



Type no. 111447 A. N. S. Phila. ; topotypes in coll. J. B. H. 



