178 THE CHICAGO ACADEMY OF SCIENCES. 
“Testa imperforata, ovato-oblonga, tenuis, pallide fusca, subtiliter 
striata, striis spiralibus confertis regulariter decussata (italics are the 
author’s) ; spira conica et acutiuscula; anfr. 4 convexiusculi, utlimus 
maximus; apertura elliptica, antice amplior, 5/8 out 5/9 longitudinis 
aequans; columella brevissime intorta; peritr. acutum, Long. 8/9, 
diam. 41% mill. Succineeformis, parum nitida.” 
This interesting little species will doubtless be found to be a 
common inhabitant of the ponds and lagoons of Cuba. 
Genus RADIX Montfort. 1810. 
1810. Radix Montrort, Conch. Syst., II, p. 266. Type Helix auricularia L. 
(sole example). 
1819. Gulnaria, Leacnu, Proofsheets, pp. 146, 148; fide Turton, Man., p. 117, 1831. 
1840. Gulnaria, Gray’s Turton, p. 232 (type L. auricularia Linné). 
1847. Gulnaria Gray, P. Z. S., p. 180 (type L. auricularia, Linné). 
1855. Neritostoma H. & A. ApAms, Genera Rec. Moll., II, p. 253, 1st sp. L. 
auricularia (Linné). Not of Mérch, 1864. 
1864. Radix Morcu, Vidensk. Meddel. Kjob., p. 302. 
1865. Radix Binney (part), L. & F. W. Sh. N. A., II, p. 30. 
1870. Radix Dati, Ann, Lyc, Nat. Hist., N. Y., IX, p. 349. 
1874. Radix HArtMAN and MicHENER, Conchologia cestrica, p. 62. 
1876. Radix Merk, U. S. Geol. Surv. Terr., IX, p. 532. 
1880. Radix Cr. & Fiscu., Mis. Scient. Mex., II, p. 52. 
1884. Radix Tryon, S. & S. Conch., III, p. 101. 
1905. Radix Dati, Alaska Mollusks, p. 64. 
1908. Radix Baker, Science, N.-S., XXVII, p. 943. 
SueELL: Broadly ovate or rounded; spire generally short, last 
whorl very large, globose, somewhat expanded or even campanulate ; 
outer lip simple, without internal thickening; columella strongly 
twisted in the earlier whorls, but the twisting frequently concealed by 
a reflexed inner lip, which may be conspicuously elevated and form a 
large, open umbilical chink; sculpture as in Lymnea (pl. XVIII, 
hig. 9). 
ANIMAL: Not differing essentially from Lymnea externally. 
Jaw: Wide and low with a heavy, broadly rounded median pro- 
jection on the ventral surface (pl. VI, fig. D). 
RApULA: First laterals tricuspid; balance bicuspid (pl. VII, 
ne C), 
GENITALIA: ‘The penis-sac is large, the penis is longer than the 
penis-sac and does not exceed the vas deferens in diameter; there is 
one penis-sac retractor which enters the penis-sac by a large, bifid 
splitting of the muscle; penis retractor narrow, about as long as the 
penis-sac retractor; it enters the columella muscle near the point of 
insertion of the penis-sac retractor; prostate not large, regularly pyri- 
