MONOPTYGMA. 91 



faint brown markings ; fasciole and interior of aperture yellowish 

 brown to chocolate. Length, 1 -5-1 '75 inches. 



Brazil to Patagonia; W. Africa. 



The young shell is much narrower in form, the contorted 

 expanded lip and heavy columellar callus indicating the adult 

 condition. 0. aquatilis, Reeve (fig. 93), and 0. contortuplicata, 

 Reeve (fig. 94), are both young shells; 0. claneophila, Duclos 

 (fig. 92) = the adult form. 



0. NANA, Lam. PI. 36, figs. 96-100. 



Conical, the upper fourth part of the body-whorl overlaid with 

 a yellowish callus, the fasciole also yellowish and obscurely 

 maculated, rest of body-whorl cream-color with chestnut longi- 

 tudinal fulgurations, often broken up into nebulous spots ; 

 columella white, interior of aperture exhibiting the external 

 colors through the shell. Length, '75 inch. 



Gabon, W. Africa; So. Africa; Madagascar. 



The West Indies have been cited as habitat for this species, 

 I think erroneously. 0. zenospira, Duel. (fig. 79^ 

 punctala, Duclos (figs. 98, 99), are synonyms. 



iTy 



Subfamily ANCILLARIIN^E. 



Genus MONOPIYGMA, Lea. 



Several systematists have confounded this genus with Mon- 

 optygma, Gray an entirely different group. The type, although 

 a very small shell, perfectly exhibits the generic characters, but 

 Lea's second species belongs to Actaeonidae. Chilotygma, H. 

 and A. Adams, must, according to the description, become a 

 synonym ; but it may well be doubted whether its only species 

 and specimen (therefore the only recent species of Monoptygma), 

 is not a monstrosity. 



M. ALABAMIENSIS, Lea.' (PI. 3, fig. 23.) Fossil. 



Eocene, Alabama. 

 M. EXIGUA, Sowb. PI. 37, tig. 1. 



Yellowish white, very shining, callous ; callously ridged on 

 the body-whorl. Length, 12 mill. 



Habitat unknown. 



This specimen formed part of the Cumingian collection. 



