OF SOUTHEFN INDIA. 
27 
armwjed in groups, but icithont any rcgxdarily, while the smaller orifices are always 
somewhul immersed and inler posed belween the others. 
The CimsciBM answer exactly to the CBRiopoiiinM, differing from the latter by 
the cells being of larger and smaller size, hotli interspersed between each other. 
"Wbetber all the generic divisions which arc introduced in it by d’Orhigny arc 
admissible I am not m a position to affirm ; hut I believe that most of the species 
of Zonopora, and its close allies, Avbieb arc placed by d’Orbigny in a distinct 
family, Caveidj!, should not be separated from the Cjibscipje, because they have 
smaller oritices placed between the larger ones, even Avben the latter only occur on 
limited portions of the stem. The name Cavewm ought, I think, to be retained for 
those genera in which the larger cells are arranged in regular series, as, for instance, 
in Cavea, Domopora, Madiopora, Stellipora, &c. 
However, some of the genera with the larger orifices arranged in bundles, or 
in multiscrial ridges, as in most of the discoid Defrancice, BusJcia of llcuss, and 
others, and also nearly the entire family Cytidab of d’Orbigny, should be united 
Avitb the Fasciforida:, or Fasciobridae, whichever name may he thought preferable. 
I have little doubt that Avith these changes, if adopted, and also those I have 
alluded to, when speaking of the tAvo previous families, a more rational grouping 
into families of the inarticulate CYCLOSTOMATA might he attained. Of 
course d’Orbigny ’s dmsion of the latter order into ‘ Foraminata, Tubulata, and 
Fascicvlatal must he given up ; for it is irrcconcileahle Avith that author’s OAvn, 
and, I helicA'e, also with any other, classification that may he proposed. 
Tavo genera, each with a single species, have been met Avith in the cretaceous 
deposits of Southern India. 
Jleteropora, BlainA'illc, 1831<. 
Colonics simple, or ramose, with cylindrical or slightly claA'ate branches, 
attached by the base to foreign objects. Larger and smaller orifices irregularly 
distributed oA'er the entire surface of the colony. 
The species of this genus are fotmd in meso- and cseno-zoic deposits, and there 
also occur a few species recent in the Eastern seas. 
Zonopora, d’Orhigny, 1849. 
Colonies ramose, as in Heteropora, hut the larger orifices only occm- in groups 
or on slightly elevated zones round the cylindrical or somewhat compressed stems ; 
there is, however, no regularity observed in their position respecting each other, 
and smaller orifices arc intermixed hetAveen them, and also occur on the intermediate 
portions of the groups or zones. 
Thus Zonopora may he looked upon as a combination of Ceriopora and 
Jleteropora. Some of the species very closely resemble Flethopora, which only 
differs by the absence of smaller orifices interspersed betAvecn the larger ones. 
The genus is met with chiefly in cretaceous deposits, hut it is also, though very 
rarelv, rci)rescnted in tertiary strata. 
( 61 ) 
