CUBAN ANNUDARIIDAE TORRE AND BARTSCH 165 



with, the axial riblets render the riblets conspicuously scalloped. Ap- 

 erture very broadly oval. Peristome double, the outer broadly ex- 

 panded and adnate to the preceding turn at the parietal wall, a little 

 wider on the parietal and inner wall than on the rest, forming a sUght 

 auricle at the posterior angle, and marked by a series of concentric 

 lamellae; inner peristome slightly exserted. Operculum typically 

 opisthosiphonid. The siphon is immediately behind the peristome, 

 short and directed backward into the suture. 



The specimen figured, U.S.N.M. No. 535348, is a paratype, which 

 was collected by Quesada on Loma de la Calera, San German. It is 

 a complete specimen having 6.2 whorls measuring: Length, 11.8 

 mm.; greater diameter, 6.6 mm.; lesser diameter, 5.3 mm. 



OPISTHOSIPHON (SOLUTAPEX?) ECHINATUM ([Gundlach] Pfeiffer) 



Plate 11, Figure 6 



1857. Cyclostomaechinatum [Gundlach] Pfeiffer, Malakozool. Blatter, vol. 4, p. 176. 



1858. Ctenopoma echinatum Pfeiffer, Monographia pneumonopomorum viventium, 



suppl. 1, p. 103. 

 1920. Opisthosiphon (Opisthosiphon) echinatum Henderson and Bartsch, Proc. 

 U. S. Nat. Mus., vol. 58, p. 68. 



Shell elongate-conic, flesh colored, unicolor or faintly spirally 

 banded; peristome flesh colored. Nuclear whorls decollated in all our 

 specimens. Postnuclear whorls inflated, strongly rounded, appressed 

 at the summit, marked by strong, lamellose, scalloped axial ribs, of 

 which 24 occur upon the first of the remaining turns in the specimen 

 described and figured, 32 upon the second, 36 upon the third, and 48 

 upon the last whorl. The spiral sculpture consists of feeble broad 

 threads, which render the riblets scalloped. Of these spiral threads, 

 5 occur upon the first, 6 upon the second, 9 upon the third, and 10 

 upon the last whorl between the summit and the suture. Suture 

 strongly constricted. Periphery inflated, strongly rounded. Base 

 short, inflated, strongly rounded, openly umbilicated, marked by the 

 continuation of the axial riblets and by 5 spiral cords, which also 

 render the ribs scalloped; within the umbilicus 6 or more additional 

 scalloped cords are present. Aperture broadly oval ; peristome double, 

 the outer very strongly expanded, partly inbent on the inner lip to 

 cover part of the umbilicus, marked by a series of concentric lamellae; 

 outer peristome adnate to the preceding turn on the parietal wall, 

 forming a conspicuous auricle at the posterior angle, behind which the 

 breathing siphon is present; inner peristome exserted and slightly re- 

 flected. Operculum paucispiral with the nucleus halfway between 

 subcentral and submarginal, marked by numerous, retractively slant- 

 ing, strongly raised, calcareous lamellae, which are fused both on their 

 inner and outer borders. 



U.S.N.M. No. 493362 contains a cotype collected at Cabo Cruz by 

 Gundlach and presented to the National Museum by Dr. de la Torre. 



