SUCCINEA. 419 



well marked; aperture ample, not less than two thirds the length of the shell, 

 well rounded at base ; columella regularly arcuated, mon; so than the peristome, 

 simple, hut its upper portion is reflexed and raised so as to form a marginal 

 wall to the aperture, as it enters the shell, and produces a slight fold where it 

 disappears within the spire; a broad, thin callus covers the left margin, which 

 is slightly detached anteriorly, so as to form the rudiment of an umbilicus. 

 Length 14 mill., of aperture 9 mill 



Succinca dmcordialis, Gould, Proc. Bost. Soc. Nat. Hist., III. 37 (Juno, 1848); 

 in Terr. Moll., II. 82, PI. LXVII. a, Fig. 2. — Pfeiffek, Mon. Hel. Viv., III. 

 16. —W. G. BiNNEY, Terr. Moll., IV. 41 ; L. & Fr.-W. Sh., I. 260 (1869). — 

 Tjiyon, Am. Joum. Conch., II. 239 (1.866). 

 Succiiiea munita, Binney, TeiT. Moll., I. in tables. 



Lake Concordia, in Texas ; a species of the Texan Subregion. 

 Jaw and lingual membrane as usual in the genus. 



Succinea luteola, Gould. 

 Vol. in. PI. LXVIL c, Fig. 1. 

 Shell of a conical, turreted form, sometimes rather corpulent, and again quite 

 slender, the last whorl being much less ventricose in proportion than the upper 

 ones, rather thick in substance ; color, when young, pale yellowish-green or 

 drab, becoming bleached or gray with dge, the interior, however, sometimes 

 having the bright yellow of yolk of egg, and always more or less tinted thus 

 when living, becoming at last dead white; surface irregularly and loosely 

 wrinkled ; whorls 4, forming a well-proportioned spire, the upper ones well 

 rounded, and separated by a deep suture, the apex acute, colored yellow ; last 

 whorl conical at its upper third ; aperture ovate, rather more than half the 

 length of shell, the columellar extremity of the peristome somewhat incumbent ; 

 columella without a fold, rounded, its edge above being seen windinsr far within 

 the spire. Length, 12|^ mill. ; breadth, 6 mill. 



Succinea luteola, Gould, Proc. Bost. Soc. Nat. Hist., June, 1848, III. 37 ; Terr. 



Moll., II. 75, PL LXVII. c, Fig. 1 (1851). —W. G. Binney, Terr. Moll., IV. 



41 ; L. & Fr.-W. Sh., I. 261 (1869). — Tryon, Am. Joum. Conch., II. 239, PI. 



II. Fig. 30 (1866). — Pfeiffer, Mon. Heh Viv., III. 16. 

 Succinea Texasiana, Pfeiffer, olim, Mon. Hel. Viv., II. 626 ; in Roemek's 



Texas, 456 (1849) ; in Chemnitz, ed. 2, 42, PL IV. Figs. 21 - 23 (1854). 

 Succinea cUrina, Shuttleworth, undescribed, teste Pfr. 



Florida and Texas ; thus belonging to the Southern Region. 



Animal not observed. 



Tliis species is very variable in its proportions, but is easily distinguished 

 from our other species by its small aperture, elongated spire, and its color ; its 

 golden interior in fresh specimens, instead of the usual silvery lustre, being its 

 principal characteristic. Its characters agree pretty well with a Mexican spe- 

 cies described by Mr. Say under the name of 6\ undulala ; and if any of our 

 species were in view in that description, it must have been this one. In form 



