1895. FEOCEE DINGS OF THE NATIOXJL MUSEUM. 31 



This species is very close to the recent Cylinlma verrillii, Dall, from 

 which it is ouly distiugaished by having- the posterior commissiire of 

 the aperture more produced and the shell a trihe more evenly cylin- 

 drical toward the apex. 



RETUSA (CYLICHNINA) QUERCINENSIS, new species. 



Shell small, resembling C. decapitata, but smaller, more solid than 

 C. decapitata of the same size, and proportionately a good deal shorter, 

 the apical pit wider, the posterior commissure of the aperture less 

 produced, the pillar shorter and more oblique and twisted, and with a 

 more distinct furrow behind it; the young G. decajntata is atteni\i\ted 

 anteriorly, but the C. quercinoisls, which is evidently adult, is not so; 

 the anterior spiral striation is barely perceptible with a glass. Longi- 

 tude, 2.5; maximum diameter, 1.25 mm. 



Habitat. — Alum Blutf beds, at Oak Grove, Yellow River, Santa Rosa 

 County, Florida, L. C. Johnson. 



Type.— 1^0. 131528, U. S. N. M. 



This species is small, but can not be referred to the young of any of 

 the other species known from the region. 



RETUSA (CYLICHNINA) DUPLINENSIS, new species. 



Shell cylindrical, surface marked with hues of growth, which are 

 slightly elevated where they pass over the ridge into the apical perfo- 

 ration, and with fine spiral stria?, which on and near the base are 

 alternated with sharper grooves; aperture narrow, as h:)ng as the shell; 

 the outer lip straight, behind but little i^roduced, and moderately 

 receding to the suture; in front the outer lip recedes and joins the 

 pillar evenly; pillar very oblifpie, strong, with an obscure plait, a small 

 chink behind the anterior end; body short, with a little wash of callus; 

 apex of the shell gently rounded over to a cylindrical perforation, with 

 little or no funicular border. Longitude, C.75; maximum diameter, 

 2.5 mm. 



Habitat. — Carolinian marl, at the Natural Well, Duplin County, North 

 Carolina (2279), Bums. 



Type.—^o. li;587(i, TT. S. N. M. 



This species differs from C. decapitata by its greater stoutness, the 

 absence of a funicle on the spire and most obviously by its stronger, 

 more oblique, and differently plaited pillar. TLe latter character also 

 separates it from C. verrillii, which differs further in having a well- 

 marked funicle around a proportionally small perforation. 



RETUSA (CYLICHNINA) MICROTREMA, new species. 



Shell small, slender, somewhat roundly pointed at both ends, smooth 

 except for lines of growth; body whorl, except distally, <inite cylin- 

 drical; aperture narrow, little produced behind, recurved directly into 

 the apical perforation without funicular fasciole or decided notch; 

 body with a slight wash of callus; pillar nearly straight, not twisted, 



