DRILLTA. J 97 



by Weinkauff to E. Africa, possibly through mistaking for it 

 poor examples of D. Barkliensis. Weinkauff attempts to sepa- 

 rate Kiener's figure of D. zebra from that given by Reeve, and 

 refers the latter, as a synonym, to D. ornata, d'Orb. ; but Kiener's 

 figure represents the ordinary West Indian form quite as well as 

 does that of Reeve. There are a number of synonyms : D. 

 albinodata, Reeve (fig. 5;, having the periphery more sharply 

 angulated than usual, the figure magnified, D. albocincta, C. B. 

 Adams, D. albomaculata, d'Orb. (fig. 11), which E. A. Smith 

 changed to D. albopustulata, under the impression that the 

 species (above mentioned) described by C. B. Adams, bore the 

 same name as d'Orbigny's, D. ornata, d'Orb. (fig. 12), D. zebroides, 

 Weinkauff (fig. 15), D. pulchra, Gray (fig. 18, magn. f), D. 

 Jayana, C. B. Adams, D. cinerea, Weink. (fig. 10), D. collaris, 

 Sowb. (fig. 7). 



As will be seen from a comparison of the above figures D. zebra 

 is a very variable species; one of its extreme forms may be 

 separated as 



Yar. LEUCOCYMA, Dall. PL 34, fig. 2. 



Compared with albomaclilata, d'Orb., it is more slender, with 

 the periphery-angle bearing a pair of close revolving ribs, more 

 conspicuous than the rest of the spiral sculpture and tipped 

 with white where crossing the longitudinal ribs. 



Sarasota Bay, W. Fla. 



In the typical albomaculata the coloring is similar, but a single 

 broader rib revolves at the periphery ; in some specimens, how- 

 ever, there is a more or less distinct impressed line on the middle 

 of the rib, so approximating it to this variety. 



D. OSTREARUM, Stearns. PL 34, fig. 79. 



Concavely, rather narrowly shouldered, with a thread-like 

 raised line at the suture, closely longitudinally ribbed below the 

 periphery, decussated by raised revolving lines ; dingy yellow to 

 purplish black. Length, 16 mill. 



W. Coast of Florida (on oysters). 



Figured for the first time, from a specimen in Coll. Acad. 

 Philad. 



D. CANCELLATA, Gray. PL 15, fig. 19. 



Whorls keeled at the upper part, transversely very finely 



T .ESLAND MUSEUM 

 ISt 



