SUPPLEl^IENTARY GONIOPOR^. 161 



This is a second Goniopora, and tliis time without doubt, from Jamaica, and these two are so 

 far the only members of tlie genus known from the West Indies. It does not appear to have 

 had any close affinity with G. Jamaicce 1. The caUcles of the latter are pronounced radial 

 structures, whereas here they are melted down into a close uniftjrm network of flakes and 

 filaments. 



a. Geol. Dept. 46811. 



SUPPLEMENT TO GROUP XIV. (Vol. IV. p. 15G.) 

 Forms without Recorded Localities. 



169. Goniopora r. h. {G. incertm sedis h.) (PI. VIII. fig. 9 ; PI. XVII. fig. 19.1 

 [Coll. Poland ; British Museum.] 



Description. — The corallum rises from a .single stout stem, into an erect, nearly ovate cluster 

 of very thick branches, showing a tendency to divide dichotomously, every division bending up 

 into the vertical, and flattening concentrically round the axis. The first cleavage passes through 

 the axis and divides the corallum righti through one of its diameters to near the Ijase, and is 

 nowhere more than 1 cm. wide. The njext division runs at right angles to tliis, a little above 

 it; above this the divisions become irtegular, ])artly because of distortion from worms and 

 Balanids. Tlie living layer is 24 cm. on one side, and 12 on the other, and there are signs as 

 if the stock had begun to lean over. 



The calicles vary in size from 2 to 4 mm. ; they are subcircular, and nearly uniformly 

 deep. The walls are stout, and stand up sharply and uuiformly thick and steep, about 1 mm. 

 over the whole corallum. In the upper parts, where the septa are u-regular, the walls are of a 

 ragged lamellate reticulum, but in the lower parts, where the septa are more regular, the 

 latter tend to striate their narrow tops ; young calicles bud on the angles of the walls all 

 over the corallum. The septa begin as a numl^er of ragged-edged ridges down the walls which 

 eventually join the columella to the wall as so many straight threads of different thicknesses, 

 not all radially arranged, nor in any well defined radial order, so that the interseptal loculi are 

 very u-regular, some large, some small, some obscured by cross threads, some angular, some 

 round. Lower down on the coral, the radial symmetry becomes gradually more perfect, and 

 the interseptal loculi, though of different sizes, are clearly definal.)le pits into the interior of the 

 coral. 



The columella is an immense tangle of lamellw and filaments, open and delicate in the 

 upper calicles, but elsewhere den.ser and sending up irregular granules and points which form 

 the typical rosette to the naked eye. 



Y 



