SUB-CLASS II TABULATA—CHAETETIDAE 103 
polygonal, all of one kind, and multiplying by fission. Uncompleted fission of 
the tubes often indicated in section by tooth-lke projection extending into 
visceral chamber. Walls structureless, without dark median line; tabulae 
complete, remote. Very abundant in Carbon- 
iferous Limestone; found also in Lias and Upper 
Jurassic. C. radians, Fisch., is an important 
rock-builder in the Russian Carboniferous Lime- 
stone, especially in the vicinity of Moscow. 
Pseudochae- 
teres, Haug; A B 
Upper Jurassic. 
a polyporus, a) 
Quenst. sp. 
& 

Monticulipora, AA ie 
VOrb. (emend. 
Nich.), (Figs. fr. 
185-187). Mas- anes 
Fic. 183. 

sive, tuberous, 
a : Chuetetes septosus, Flem. Carbonifer- 
hemisp herical, ous Limestone; England. A, Transverse 
ISeold: ne section parallel to upper surface. Chaetetes radians, Fischer. Carbonifer- 
discoidal, Yra- B, Vertical section, both enlarged ; ous Limestone; Moscow, Russia. Portion 
“mose or en- p, Projecting spines representing .un- of longitudinally fractured corallum, 
: completed fission (after Nicholson). natural size. 
crusting coralla 
of extremely variable form and size, and composed of numerous, fine, tubular 
corallites, usually of two series, the walls of which are imperforate and closely 
approximated to one another, but are not amalgamated. Multiplication by 
intermural gemmation, more rarely by fission. Tabulae horizontal, and either 
complete, extending entirely across the visceral chamber, or incomplete ; in the 
latter case the spaces where tabulae are not developed are filled with large 
(6: D 


tated [| L | 

Fic. 185, 
Monticulipora (Heterotrypa) ramosa, EK. and H. Ordovician (Cincinnati Group); Cincinnati, Ohio. 
A, Corallum, natural size. 6, Surface slightly magnified. C, Tangential section, parallel to external surface, 
20/;. D, Vertical section, 20/;. (Cand D after Nicholson.) 
cystoid calcareous plates. The walls differ from those of Chwetetes in that they 
are composed of two distinct lamellae separated by a dark or light median line, 
and are sometimes thickened by deposits of carbonate of lime. The corallites 
are polygonal or round in contour, and, as a rule, two series are distinguishable ; 
a series of larger tubes with remotely situated tabulae, and another series of more 
or less numerous interstitial tubes, which are smaller and more closely tabulate 
than the former. The larger tubes (utopores) are often surrounded on all sides 
