a 
BELLEROPHONTIDA. 32: 
BucantiA, Hall, 1847. 
Syn.—Phragmostoma, Hall, 1862. Centrotheca, Salter. 
Shell planorbiform, the whorls exposed equally above and 
below, with revolving striew; last whorl much enlarged at the 
aperture. Silur,, Carb. B. expansa, Hall (1xxxii, 100, 1). 
BUCANELLA, Meek. Shell without slit-band. 
TROPIDOpIScUS, Meek. Strongly compressed, disciform, widely 
umbilicated, with a high keel and very short incision in the outer 
lip; callosity on the inner lip very little developed. Silur., Carb. 
B. curvilineata, Conr. (1xxxii, 2, 3). 
TREMANOTUS, Hall, 1864. (Salpingostoma, Roemer, 1876.) Like 
Bucania, but in place of the slit-band, a row of oval openings on 
thelast whorl. Mouthstrongly expanded. Silurian. 7’. alpheus, 
Hall. 
TUBINA, Barrande, 1868. Like Tremanotus, but with three 
rows of openings instead of one, on which long hollow tubes are 
placed. Mouth very little expanded. Silurian; Bohemia. 
EUPHEMUS, M’Coy, 1844. Umbilicus absent or small, shell 
with spiral folds, not continued on the last whorl, aperture 
slightly contracted, lip sometimes emarginate, no distinct slit- 
band. Carb.; Gt. Brit., Salt Range, India. B. (Huphemus) 
Indicus, Waagen (1xxxii, 4). 
TROPIDOCYcLUS, Koninek, 1882. 7. curvilineatus, Conr. 
STACHELLA, Waagen, 1880. More or less globular, smooth, 
unsymmetrical, mostly umbilicated on one side and with a closed 
umbilicus on the other; slit-band distinct, but superficial, slit 
shallow. Fossil... Salt Range, India. B. bifrons, Waagen 
(Ixxxii, 5, 6). 
PHRAGMOSTOMA, Hall, 1861. Mouth much expanded, with the 
slit forming a sinus; slit-band well marked; inner lip expanded 
into a septum. Devon.; New York. Is very closely related to 
Carinaropsis, Hall. 
BeELLeropuina, d’Orb. 
Distr.—Cretaceous; Europe. B. Vibrayi, d’Orb. (1xxxii, 7). 
Shell subsymmetrical, globular, the whorls embracing as in 
Bellerophon, but without sinus ; sides slightly unequal, the spire- 
whorls perceptible above, while below the umbilicus is very 
narrow. 
Carinaropsis, Hall. 
Distr.—Fossil,2sp. Silurian; America. C. carinata, Hall. 
Shell having a patelloid aspect. Spire usually attenuated ; 
body-whorl expanded abruptly; cavity shallow, presenting a 
kind of septum as in Crepidula. 
Cyrro.itEs, Conrad. 
Etym.—Kurtos, curved, lithos, stone. 
Mstr.—Fossil, 13 sp. L. Silur—, Carb.; N.Am., Eur. C. 
ornatus, Conrad. 
