ART. 22 MIOCENE GASTROPODS AND SCAPHOPODS MANSFIELD 17 



the latter is more open and possesses nodules at the intersection of the 

 axials and spirals. 



Occurrence. — Middle or lower Miocene; Guaico-Tamana Road, 2 

 chains east of mile 13 from junction with Eastern Main Road, Trini- 

 dad, British West Indies. 



DRILUA CONSORS TRINITATENSIS, new subspecies 



Plate 3, figs. 12, 13 



Shell rather small, moderately stout, fusiform, with five remain- 

 ing whorls on the larger cotype, smaller cotype with anterior whorl 

 of nucleus partly intact; spire whorls slightly inflated; suture 

 shallowly grooved and loosely appressed; anal fasciole rather wide, 

 shallow and marked by two to three spiral threads and close-set 

 arcuate growth lines. Nucleus, as revealed, inflated and smooth. 

 Axial sculpture of postnuclear whorls (12 on the penultimate 

 whorl of larger cotype but other specimens have up to 17) slightlv 

 protractive, rounded ribs, stronger than the spirals, and extending 

 from the anal fasciole forward to the suture. Spirally sculptured 

 in front of the suture with a keel and, between the anal fasciole 

 and forward suture on the earlier whorls, with four close-set 

 threads and, on the latter whorls, with four low, close-set threads 

 separated by stria, all scarcely overrunning the axials. Base 

 similarly sculptured except that the striae between the spiral 

 threads shallowly incise the ribs. Outer lip broken away at the 

 margin; pillar with wash of callus, nearly straight and slightly 

 reflexed anteriorly. 



Dimensions: Larger cotype (U. S. Nat. Mus. Cat. No. 352629) 

 measures: Height 13 mm.; greatest diameter 4.3 mm. 



The ncAv subspecies here described is represented at only one lo- 

 cality and differs from DriUia consors., subspecies hiiUhroohl in 

 possessing close-set crowded spiral sculpture and the absence of 

 nodules at the intersections of the axials and spirals. 



Pleurofoma alesidota^ var. magna Bose, from Paso Real cerca de 

 Tuxtepec, Oaxaca, is very closely related to the neAv subspecies, but 

 it is a larger and stouter shell than the Trinidad form. 



Occurrence. — ^Middle or lower Miocene: In flood-wash, 1 mile 

 south of Brasso, Trinidad, British West Indies. 



DRILLIA PENNYI. new species 



Plate 3, fig. 2 



Shell small, solid, surface glazed ; axial sculpture over the body of 

 the w^iorl more prominent than spiral; with two and one-half 

 nuclear and seven postnuclear whorls; whorls inflated and tightly 

 constricted at the suture. Suture moderately appressed and wavy; 

 anal fasciole wide, undulating, slightly inclined posteriorly. Nu- 



