432 
BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 
cell opening into the peristomie. In the Smittiniclae the peristomie is formed by 
the development of a peristome with spines ; in the Stomachetosellidae it is formed 
by the thickening of the frontal. 
We have founded our generic classification on the aspect of the ovicell and on 
the variations of the escape of the larvae, an important function. All the other 
A. Stomachetosella 
B. Enoplostomella 
C. Metradolium 
D. Schizemiella 
E. Leiosella 
F. Metrocrypta 
G. Ochetosella 
Fig. 129. — Genera of Stomachetosellidae Canu and Bassler, 1917. 
A. Stomachetosella crassicollis Canu and Bassler, 1917, X 20. Vicksburgian of Alabama. 
B. Enoplostomella defixa Canu and Bassler, 1917, X 20. Vicksburgian of Alabama. 
C. Metradolium obliquum, new species, X 20. Jacksonian of North Carolina. 
D. Schizemiella claibornica Canu and Bassler, 1917, X 20. Claibornian of Alabama. 
E. Leiosella rostrifera Canu and Bassler, 1917, X 20. Vicksburgian of Alabama. 
F. Metrocrypta bucculenta Canu and Bassler, 1917, X 20. Middle Jacksonian of North 
Carolina. 
G. Ochetosella jacksonica Canu and Bassler, 1917, X 20. Middle Jacksonian of North 
Carolina. 
functions, reproduction, hydrostatic, calcification, and passage of the eggs, remain 
exactly the same. 
Genus STOMACHETOSELLA Canu and Bassler, 1917. 
1917. Stomachetosella Canu and Bassler. Synopsis American Early Tertiary Cheilo- 
stome Bryozoa, Bulletin 96, United States National Museum, p. 45. 
The ovicell entirely surrounds the apertura. The frontal is a tremocyst with 
wide-mouthed tubules. No avicularia. The peristomice of the ovicelled zooecia 
possesses a straighter rimule-spiramen. 
Genotype. — Stomachetosella crassicollis Canu and Bassler, 1917. Vicksburgian. 
