34 • MADKEPORARIA. 



by a boring alga. The clearness with which these hollowed parts of the skeleton can still he 

 seen is a further argument against the suggestion that the fossil has been secondarily altered. 



o. Geol. Dept. R 9816. 



Other forms recorded from Trinidad are : a fossil from St. Croix, said by Duncan * to be 

 synonymous with Pontes Collegniana = (Goniopora Turin 1 f), and a recent astrceoides (that 

 is, massive) form, not described, apparently because calling it " Astroides " was thought to be 

 sufficient ! 



11. Porites Barbados 1. (P. Barhatm prima.) 

 [Barbados, coll. Wilkes Expedition, 1838-1842.] 

 Syn. Porites flexuosa Dana, Zooph. (1848) p. 554, pi. liii. fig. 6. 



Description. — The corallum forms short tufts of flexuous branches, divaricate, and swollen 

 at the tips, which are very blunt or sub-truncate, or at times sub-flabellate. The branches are 

 from 1 • 2 to 1*6 cm. thick ; when flattened at the tips they may be 2 • 5 cm. broad. The living 

 layer is 6 cm. deep. 



The calicles are large, about 1 • 5 mm. in diameter, shallow, with flattened floors. The 

 septa are obtuse and (?) project one-third of the way across the calicle. 



The corallum is very porous and with spongy apices. 



There is, in the National Collection, only one branching form from Barbados, which 

 produces small, branching tufts with divaricate forkings. But the measurements show it to 

 be a much smaller form with smaller calicles than this coral of Dana's. The spongy tip and 

 consequent reticular axis is characteristic of all branching Porites, but seems to be especially 

 developed in the Barbados forms (cf. e.g. P. Barbados 6). This character is not shown in 

 Dana's figure, which merely represents a single slightly curved terminal. The remark that 

 it is not unlike P. clavaria is too vague to be of any use. The specimen is referred to by 

 Dr. Eathbun in hia " Catalogue of Porites."J 



12. Porites Barbados 2. (P. Barhatce secunda.) (PI. I. fig. 8 ; PI. XV. fig. 5.) 



[Barbados, coll. Gregory ; British Museum. 



Syn. ? Poiites furcata Dana {non Lamarck), Zooph. (1848) p. 555. 



Description. — The corallum forms tufts of thin, somewhat tortuous, divaricate branches, 

 varying from 8 to 12 mm. thick, round or compressed. The forking is quite irregular : one 

 prong frequently aborts, with the result that most of the branches show sudden, almost 

 angular bends. Stems frequently appear to divide into three branchlets. The tips of the 

 terminals were either round or greatly flattened. The living layer is about 3 cm. deep. 



• Quart. Joum. Geol. Soc, xxiv. (1867) p. 25. f Vol. IV. p. 117, of this Catalogue. 



I Proc. U.S. National Museum, x. (1887) p. 354. 



