Zoopuyta.] UPPER PALAZOZOIC RADIATA. 81 
The small size of the cells and mode of growth seem somewhat analogous to the Russian 7. concinna 
(Lonsd.) and separate them at a glance from the three other published species; but the present species 
differs in its vesicular plates not being nearly flat and horizontal, but much curved and variously inclined. 
Position and Locality—Common in the carboniferous limestone of Derbyshire, forming subcylindrical 
masses three or four inches long. 
Explanation of Figure.—Plate 3. B. fig. 14. Portion of large mass natural size, from Derbyshire, with 
a rough section of one corner, and a polished section below. 
MICHELINEA GRANDIS (/°Coy). PI. 3. C. fig. 1. 
Reef —M°Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 123. 
Sp. Ch.—Corallum widely conic, the width considerably exceeding the height, externally marked with 
thick, rounded, radiating ridges, finely wrinkled across ; polygonal cells, on the upper convex surface, averaging 
five to eight lines in diameter (most near the former at a height of half an inch, most near the latter size at a 
height of two inches), very deep, with thin walls not coated by vesicular plates, but having numerous distinct 
foramina, and many longitudinal strize within; internal vesicular plates small, very thin, much curved, form- 
ing nearly horizontal irregular rows of vesicles at the bottoms of the cells. 
This fine species is most allied to the J/. tenuisepta (Phill. sp.), but is distinguished by the much wider 
conical form of the mass, and by the cells having, on an average, a diameter three times greater at the 
same height than in that species, of which I have examined many specimens both British and foreign, and 
find the figures of Michelin and Koninck, as well as of Prof. Phillips, exact in this respect. Young speci- 
mens (one to two inches in diameter) slightly resemble the IZ. favosa (Gold. sp.) in form, haying the base 
much flatter than in the adult; but on comparison with authentic Belgian specimens, thay are found to be 
distinguished by the large, rounded, radiating ridges on the exterior, of which no traces exist in that species, 
as may be also seen from the figures of Goldfuss and Michelin ; the cells also of the present coral are, even at 
that stage larger, and increased growth destroys all resemblance. 
The M. megastoma (Phill. sp.), which has large cells (although much less than the present species), 
is distinguished by its mode of growth, it forming large flattened expansions ; internally its vesicular plates 
are much larger, fewer, and highly inclined at the circumference, coating the walls of the cells to their very 
edge, giving them a peculiar thick tumid appearance, which may be imperfectly recognised in the worn 
specimens figured by Prof. Phillips, but which distinguishes even fragments from the other four species. 
Average height of the conical masses two and a half inches, width, three and half inches. 
Position and Locality—Very common in the carboniferous limestone of Arnside, Kendal; carboniferous 
shale, Isle of Man. ; 
Explanation of Figures —Plate 3. C. fig. 1. Natural size, from Arnside, some of the cells shewing the 
vertical internal striz and connecting pores; one of the external walls, slightly worn, shews the internal 
vesicular structure. 1a@. Do. Vertical (and of some of the columns slightly oblique) sections, shewing the 
internal vesicular plates, and the foraminated structure of the walls. 
Subfamily. Cumrretina. See page 24. 
Genus. CHASTETES (Fischer as defined by Lonsd.) 
Gen. Char.—Corallum polymorphous, composed of closely aggregated, prismatic, capillary tubes, inse- 
parably united, crossed at variable distances by transverse diaphragms; no connecting tubuli or foramina 
in the sides; increase by splitting of the old tubes into two or three, the divisional walls arising from 
the middle of a side (not from the angles). 
Erroneously supposed by Fischer to differ from /avosites by the want of transverse diaphragms, but 
the true characters of the well-preserved Russian type has been well developed by Mr Lonsdale (Geol. 
of Russia, Vol. I. p. 593). 
M 
