248 EEV. E. BOOG WATSON OS THE 



stronger on tlie base, and still more so on the snout. Colour 

 that of pale flint when seen in thin flakes. Spire high, narrow, 

 conical, scalar. Apex consists of 1| embryonic whorls, which form 

 a blunt, smooth, small top, with the extreme tip somewhat im- 

 mersed ; these whorls are very finely, but not quite regularly, 

 microscopically spirally scratched. WJiorls nearly 9, rather short, 

 with a drooping shoulder and a blunt carination, from which they 

 contract with a scarcely convex profile to the lower suture ; the 

 base is conical, very lop-sided, scarcely convex, and prolonged 

 into a very short snout. Suture sharp and well-defined by the 

 swelling of the whorl above, and by the row of tubercles round 

 the top of the whorl below. Mouth oblong, a little oblique, 

 pointed above, prolonged into a shortish oblique canal below. 

 Outer Up well arched, with a very slight and open sinus above. 

 Inner lip — a very thin glaze runs across the concave line of the 

 body and down the pillar, which is obliquely cut off in front and 

 has a twisted and slightly patulous inner edge. H. 0'65. B. 021, 

 Penultimate whorl, height 0-11. Mouth, height 0-25, breadth O'l. 

 In general form this species is slightly like a large Pleurotoma 

 cerinum, Stimp. and Kurtz, but is obviously quite distinct. It is 

 a good deal like P. (D.) tholdides, "Wats., but is more scalar, is 

 smaller in the apex, longer in the base, and different in sculpture. 



66. Pleurotoma (Deillia) tholoides, n. sp. (doXoeidrjs, dome- 

 shaped, see the apex.) 



St. 122. Sept. 10, 1873. Lat. 9° 5' S., long. 34° 50' W. Off 

 Pernambuco. 350 fms. Mud. 



Shell. — High, narrow, conical, ribbed, strong, with a rather 

 short conical base, a very blunt dome-shaped apex, and having 

 the texture and colour of flint. Sculpture. Longitudinals — there 

 are on each whorl about 17 not very distinct, narrow, slightly 

 swoln ribs, which are a little convex backwards ; they run from 

 suture to suture, but die out on the base, and toward the mouth 

 they become a little crowded and indefinite ; besides these there 

 are a great many fine, regular, hair-like Hues of growth. Spirals — 

 there is on each whorl, above the middle, an angulated carination, 

 bearing a thread on its top, which rises into rounded low tuber- 

 cles where it crosses the ribs ; below this, a little above the middle, 

 is another thread, finer, less prominent, and with feebler tubercles, 

 which also marks a slight keel ; three other threads of about the 



