or SOUTIIEEN IXDIA. 
11 
Fomily—TUAMNASTllEIDJE. 
Prof. E.CUSS suggested* the separation of this family from the true Ahtheidm, 
particularly referring to it the two genera Thamnaslrea and Dimorpliaslrea. Both 
have a compound corallum with extra ealieular gemmation, hut the calyces are eon- 
tiuent with their septo-eostae, and internally the septa are at regular distances connect- 
ed by transverse lamellae, which have a far greater resemblance to the synapticulac 
of the Fuxgid/e, than to the dissepiments of the Astreidm, and thus the present 
family may be regarded as a connecting link between the two last named ones. 
lleuss adds (1. cit., p. 21,) a new genus Pseuclastrea, with the type species Fs. 
columnaris from tertiary beds in Styria ; and, I think, the genus Comoseris, which 
has very distinct synapticuhe, might be added. Promentel appears to refer to the 
present family under the name ‘ Comoseriniens’ on p. 159 of Pal. Prang, terr. cret., 
vol. viii, 18G3. 
I have to report from South India upon four species of Tliamnastrea, one of 
Fimorpkaslrea, and one of Comoseris. 
XIX. TIIAiVEXASTREA, Lesauvage, 182.3. 
* Hist. Nat. (les Corall., vol. ii, p. 55.5. 
Corallum very variable in form and size, globular, conoid, or with the upper 
surface flattened, or forming branched stems, on which the gemmation is submar- 
ginal. The calyces are superficial, connected in all directions with each other by 
their septal costm ; their centres arc, however, distinct, with a more or less well 
developed columella; they are irregularly distributed over the entire surface. The 
septa and costm are granulated laterally, and very variable in number. 
The species arc all fossil, extending from the mesozoic into the kainozoic epoch, 
though very much decreasing in number in the latter. There exists a remarkably 
great similarity between the different species, and as the size and form of the 
calyces often vary on different portions of one and the same corallum, the precise 
definition of the species is accompanied with no small amount of difficulty, or 
rather uncertainty. This may be gathered from the fact that the authors of the 
Hist. Nat. dcs Coralliaires relate about 30 doubtful species, Avhich had in former 
years been established by themselves. 
I have to notice from South India five species. Unfortunately the materials 
are such, that although the specific distinction cannot be questioned, I am unable 
to pronounce any of them as identical Avith formerly described species. 
1, Tjiamxasthea hieroglypiiica, Stoliezka. PI. VIII, Eig. 5, 
Thamnasl. corallum plus minusre regtilarilcr orhiculare, supi'a fere planum, 
infra convexiusculurn, calijcihus numerosis irregulariler dispositis, impressis, versus 
peripheriam concenlrice approximalis, 3 ad 5 mni. latis, aUpie 7 ad 10 mm. 
* Denkscli. Akad,, Wien, Alalh. Xat. Klasse, vol. xxili, 1801, p. 23. 
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