32 EEV. E. BOOG WATSOW ON THE 



3. PUNCTURELLA AGGER*, 11. sp. 



St. 24. March 25,1863. Lat. 18°38'30" N., long. 65° 5^30" W. 

 OflP St. Thomas, north of Culebra Island, Danish "W. Indies. 

 890 fnis. Coral-mud. 



Shell. — Small, porcellaneous, oval, broader in front ; side slopes 

 straight, the front convex, the back concave, rather high, but 

 with the top depressed and thrust out backwards, yet little pro- 

 jecting, the apex being Hattened out on the posterior slope ; there 

 are many not crowded slight radiating ribs set with stumpy 

 prickles ; the long and lanceolate slit is on the crest, and from it 

 a ridge runs down the front slope. Sculpture. The riblets are 

 very slight, but are made distinct by the little triangular jjrickles 

 which pretty closely stud them ; these prickles more irregularly 

 and remotely tally v\'ith feeble lines of growth ; the ridge down 

 the front slojDe is small, and is crowned with two ojf the riblets 

 parted by a narrow furrow ; these riblets along hhe slit rise 

 into sharp laminae. Colour : the shell is porcellaneous white, 

 with a slight ruddy tinge. Apex somewhat depressed and shortly 

 projected backward, curling in on the central line of the shell, 

 but with the extreme tip flattened-out on the posterior right 

 slope ; there are 21- whorls in all. Slit lies high on the front 

 slope, distant from the apex about once and from the margin 

 about twice its own length ; it is long and narrow, bluntly 

 rounded at the upper end, and produced in front to a long sharp 

 point. Margin is thin and not fretted with tlie rib-ends. Inside 

 glassy, deeply hollowed into the apex, feebly rayed, and having 

 the rays picked out with bright specks corresponding to the ex- 

 tenal prickles : a long shallow furrow, bordered by a minute ridge 

 on either side, runs widening upAvards from the margin to the slit, 

 which is covered in all its length by the somewhat contracted, 

 sinuous-edged, cross-scored, straight, glassy septum, which arches 

 in to the apex. L. 0-17. B. 0-13. H. 0'09. 



This species has somewhat the form of P. tulerculata, but is 

 not so compressed, and the sculpture is quite different, 



4. PtiNCTTJETiLLA BiiTCHiA, u. sp. {jopvxios, deep sca.) 

 St. 47. May 7, 1873. Lat. 41° 15' N., long. 65° 45' W. Oft' 

 Halifax, Nova Scotia, 1340 fms. Mud. 



Shell. — Very small, porcellaneous, translucent, oval, very 



* So called from the little ridge that runs down from the front slope of the 

 ehell from the slit. 



