Description - Add description
|Perichlamidium venustum (Bailey 1856; pl. 1, figs. 16-17):|
Shell discoidal with a thickened spongiform central mass, and a broad cellulose margin with numerous rays prolonged into projecting spines.
Diameter 10m to 15m. Width of margin 1m to 2m.
(The micro-unit which I employ is 1/1000th of an English inch, and I express the dimensions in integers and fractions of this unit, thus 3 1/4m=0.00325”)
[Diameter =0.010 to 0.015 inch. Width of margin= 0.001 to 0.002 inch].
This shell is not rare in these soundings, and is, I believe, the first of its genus that has been found in the recent state.
|Benson, 1966, p. 210-213; pl. 10, figs. 2,4,7 (not figs. 3,5(?),6):|
Ommatodiscus sp. [part.]
See Benson (1966) description of this species group under Stylodictya tenuispina.
Benson, 1983, p. 509 [revised 2003]:
Stylochlamydium venustum (Bailey)
This species includes specimens with an opaque, biconvex central region (concentric discoidal shells), surrounded in a single plane by generally irregular concentric rings which may be broken into concave outward segments near the periphery of the test. A porous sieve plate covers the rings on both sides of the test.