PROUT—BRYOZOA, 3D SERIES. 443 
Third Series of Descriptions of Brrozoa from the Pale- 
ozoie Rocks of the Western States and Territories. 
BY H. A. PROUT, M.D. 
SEMICOSCINIUM, n. g. 
Bryozoum, a leaf-like expansion, somewhat penniform with- 
out a shaft; sole formed of longitudinal and horizontal paral- 
lel ridges, surmounted by a cellular tissue, divided perpen- 
dicularly by thin longitudinal septa, corresponding to the 
Bryozoum, a flat, leaf-like expansion, abit one lime in 
thickness, distinetly penniform a about two inches from its 
wer border, longitudinal rays (lateral) irregularly thicken- 
ed or expanded, waved, or sharply flexuous, leaving the me- 
ut 65°. — =o anak ws 
rays, expanding obliquely downware : 
ee ee ees on 
ting i 
rays at an angle of about 65°, both erossing the longitudinal 
ridges, and tortuous tubes, at an acute angle. Fenestrules 
round & cen 
- @iprea vhich have been formed of larger 
o ‘ells; sole formed of ridges, longitudinal to what uid te 
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