SCALID^ OF THE WEST INDIA ISLANDS. 195 



Long. 15:1^ mm.; lat. 7 mm.; alt. aperturse 5 mm. 

 Scalaria denticulata, Sowb., Thes. p. 87, t. 32, f. 25-26 (non Mg.) 

 Hob. Anguilla (H. Krebs); St. Thomas, St. Croix (Hornb., Swift, Riise, Kvebs), 



Bahama (E.iise). 



Chiefly distinguished by its beautiful decussated sculpture between the ribs, 

 arising from the filiform spiral lines of various thickness, generally alternating, 

 every second, third, or fifth being thicker; and the lines of growth, which are very 

 thin and capillaceous. 



Sect. **. Costis undulato-dentatis. 



10. ScALA SOLUTA, Dkr., n. sp., PI. 29, fig. 5. 

 T. umbilicata, Candida, polita, abbreviato-turrita ; anfr. primi Isevigati, sntura profunda, ult..tres 

 soluti ; costaj x in anfr. ult., lobis 4, parvis per paria digestis, posteriores 2 majores. Aper- 

 tura circularis, labro lobato. 

 Long. 5 mm.; diam. 2^ mm. 



Scalaria soluta, Dkr., MSS. in Mus. Riise. 

 Hab. St. Thomas (Krebs); Smith's Bay (Riise). 



Scala hyalina, Sowb., Thes. fig. 21, from the Philippine Islands, is the nearest 

 allied species. 



11. SCALA ECHINATICOSTA, D'Orb. 

 T. abbreviato-turrita, lactea; anfr. tres primi Isevigati, adnati, cseteri soluti; costai quadrilobatai, 

 in anfr. ult. xii. Apertura soluta, circularis, labio 4- vel 5-lobato. 

 Long. 3^ mm. ; lat. 2 mm, 



Scalaria echinaticosta, D'Orb., Cuba, 2, p. 18, t. 11, f. 4-6. 

 Hab. St. Thomas (Swift, Riise). 



Var. a. Blandii, PI. 29, fig. 8 

 T. abbreviato-turrita, lactea, perforata; anfr. disjunct!; costse x in anfr. ult., hue illuc continuoe, 

 foliacese, vix reflexge, margine undulato-lobato. Apertura soluta, pisiforrai-ovalis. 

 Long. 5i mm. ; diam. 2 mm. 



Hah. St. Thomas (Krebs). 



The variety differs in having the suture less open, the lobes on the ribs smaller 

 and more numerous; sometimes the ribs are continuous from one whorl to another. 



12. Scala volubilis, Morch. 

 T. anfr. valde discreti, costis xiii in anfr. ult. brevissimis, undulatis, vix lobatis. 

 Long. 4 mm.; diam. 2 mm.; apertura diam. 1 mm. 

 Hab. St. Thomas ; specimen unicum spira fracta (H. Krebs). 

 Scala hyalina, Sowb., Thes. fig. 22, is very like to this species. 



