26 CRETACEOrS COEALS OR ANTHOZOA 
XII. Genus. — ASTROCffiXIA, Ilihie-Edwards and Uaime, 1818. 
Hist. Nat. clcs Corall., vol. ii, p. Sul. 
Compact coralla of a globular, sub-globular, or more or less ramified shape, ou 
Avbicb tlie calyces are irregularly distril)utcd and close together, polygonal, separated 
by granules or rudiments of septal costae ; the columella is styliform, solid, somewhat 
projecting in the middle of the calyx; the septa are granular, arranged in six 
cycles, but sometimes apparently in eight or ten, some of those of the second cycle 
being equally strongly developed as those of the first. 
The species of this genus only differ from Styloccenm by the want of projec- 
tions at the angles between the calyces, and as these become occasionally or locally 
in some (particidarly tertiary) forms of the latter genus obsolete, several authors 
consider the distinction of the two genera as doubtful, suggesting that the character 
alluded to should only bo used as facilitating an easier grouping of the species, all 
referable to one genus. The ramose species have been called Enalloccenia by 
d’Orbigny, but the mere mode of growth is justly rejected by Milne-Edwards 
and Ilaimo as a character of generic Avalue. 
Renss first observed the granulation of the septa. In Ast. KonineJd or deca- 
2 diylla of the Gosau, for instance, the granulation of the upper edge of the septa is 
very distinct, and the genus must, therefore, be transferred from the Sttlixidje to 
the STMriiYLLix/E, treated by Milne-EdAvards and Ilaime as a sub-family of 
the Astkeiv/e. 
The tyihcal species of Astrocoenia arc knoAvn from mesozoic and cainozoic 
deposits. Only recently a few recent species had been referred to it, but they 
apparently require a A'crification of the generic determination. Pour tale’s (Illust. 
Cat. Museum Comp. ZooL, No. iy. Deep Sea Corals, 1871, p. 09,) describes a ncAv 
recent species as Ast. pectlnata, incrusting the base of a Madrepora. The author 
says in the description “ costse spinous, generally not confluent,” colmnclla 
rather stout, conical, holloAV, free to a considerable depth; calyces 1'5 mm. 
wide. 
The species occurring in the South Indian cretaceous deposits arrange them- 
scIa’OS as follows : — 
a. 1. AVitli six primary septa — in three complete cycle.s, — calyces 2 — 3 mm., A. retifera, n. sp. 
2. „ „ „ — in two C 3 xles — calj'ces 1'2 to 1'75 mm., A. Eeii^siana, n. sp. 
3. „ „ „ — „ „ calyces 1 mm., .4. n. sp. 
1. 4. AVith ten principal septa — in three complete cycles — A. deeapltt/lla, Mich. 
1. Astroccexia retifera, SloUczlca. PI. V, Pig- 2. 
Astroc. corallum crassum, semi-glohosum, aut tiiherosiim ; calioihus attingenti- 
hus, polygonis, fplerumque irregulariter hexagonisj 2 ad 3 mill, latis, niargimhus 
nnilis elevatis, tubercxdis crassiuscuUs omiatis ; sep)iU in tribus cyclis perfectis 
( 158 ) 
