SYNOPSIS OF GENERA. 
Family, Lepadid^. 
Genus STROBILEPIS, nov. gen. 
Diagnosis. Capitulum composed of 
four vertical ranges of plates, having in 
general a trihedral form, but varying 
greatly in contour and size. Each plate 
is closely articulated to, and sometimes 
overlapping the next preceding. The 
anterior extremity is terminated by a 
relatively large, circular, conical plate, 
against the sides of which the first plate in each vertical range lies. In the 
type species, two of the four vertical ranges of plates are of about the same 
size, one consists of a few very small plates and the fourth is modified into a 
series of spines which appear to be articulated to one another at their bases 
and to lie opposite the range of small plates. Plates calcareous and relatively 
thick. Surface ornamented by fine concentric, often obsolete wrinkles of 
growth, and low radiating furrows and ridges, and entirely covered with minute 
punctm. 
Genus TURRILEPAS, Woodward. 1865. 
1865. Turrilepas, Woodward. Quai-t. Journ. Geol. Society. 
1872. PlmnuUtes, Barr.andb. Syst. Sil. Boheme, vol. i, suppl. 
1875. Plumulites, Hall and Whitfield. Geol. Surv. Ohio, Palieontology, vol. ii. 
1876. PLumuUtes, C. F. Rcbmbr. Lethiea palieozoica. 
1882. Plimiulites, Clarke. Amer. Journ. Science. 
1882. Plumulites, rnTm-E-hT). Ann. New York Acad. Sciences. 
1884. Plumulites, Zittbl. Sitzungsber. d. math.-phys. Classe d. k. bayer. Akad. d. Wiss. 
1885. Plumulites, Zittbl. Handb. d. Palieontologie. 
Diagnosis. Elongate cone-shaped bodies, composed of from 
four to six vertical ranges of scale-like plates, which are sub- 
triangular in general outline and are covered with strong, some¬ 
what elevated concentric lines. The plates of the middle range 
are distinguished from those of the lateral ranges by their more 
convex surface and median carina. (zittel.) 
Turrilepas Wrightiaiius. 
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