AUSTRALIAN PORITES. 135 
The calicles appear very small, under 1 mm., flush with the surface, or very slightly 
depressed, and angular. The walls show a faint indication of being raised ; on the top surface 
they are in complete rows of very delicately jagged or frosted granules, allowing free com- 
munication between adjacent interseptal loculi; round the lower sides they consist of delicate 
flat flakes perforated in single or double rows, and with delicate frosted granules scattered 
over them ; they are thus reticular. The septa are rendered conspicuous by their pronounced 
lateral echinulations, The echinule may be grouped so as to form both wall granules and small 
septal granules. Within the angular areas between the slightly raised polygonal walls of the 
ealicles, and the circular fossa, the septa seem to rise from shelves of flat flakes. The pali, 
very echinulate or frosted, are usually present as the five principals, with the dorsal directive 
sometimes added as a small plate or knob. The central tubercle is mostly conspicuous as 
a round or flattened granule on a level with the pali, or else it is quite absent, leaving a 
pin-hole fossa, 
The section shows long regular trabeculz, not very crowded, joined together very irregularly 
in the central axis of the stock, but more regularly and with stouter elements down the sides. 
The colour of the unbleached stock is a pale brown. 
The photographic magnification shows the top ridges of the walls and septa very clearly, 
owing to the fact that the specimen was lighted from the side. In reality the specimen looks 
white and solid, seen from above, with no such deep interseptal loculi as shown in the 
photograph. 
This is a very instructive specimen. It has been fractured so as to ishow part of the 
epithecal film of the original colony, a vertical section through the stock, and also the fact that 
at one period the surface had been largely killed down and was grown over by a fresh layer, 
the rapid thickening of which can be readily seen. Important, also, is the fact that the internal 
texture varies, for in the central axis where growth is most rapid, the trabeculz are loose and 
long, and very irregularly joined by horizontal elements; but down the sides the texture is 
more compact, and the two elements are more equally developed. 
The echinulation of the surface elements gives the coral a kind of bloom, which recalls the 
somewhat similar type of calicle of P. Bay of Panama 1. (See Pl. X. fig. 3.) 
a, Zool. Dept. 97. 3. 9. 217. 
No. 37 ought to have been described here. It is, however, associated below with Nos. 35 
and 36, on account of the character of the growth-form, 
The occurrence of a large stag-horn shaped Porites, 4 to 5 ft. high, on the steep edges of 
reefs in the Torres Strait, is mentioned in a footnote on p. 117. 
