l88 PAPERS FROM THE DEPARTMENT OF MARINE BIOLOGY. 



The following is Bernard's redescription of Quelch's figured type of Rhodarcea 



tenuidens : 



"The coralUim massive, smooth, oval, apparently built up by successive cushion-like 

 growths (see introduction, p. 24, fig. 2c), each consisting of a thick (ca. 2 cm.) layer with 

 bulging sides, and with its edge tending to curl under and not to envelop the whole stock. 



"The calices are 3 mm. in diameter, subcircular, with cylindrical fossae of varying 

 depths up to 3 mm. Wall of unequal thickness, the thinner parts very thin, fragile, and 

 so fenestrated as to form an open lattice-work with frilled ragged edges; the thicker parts, 

 seen from above, are a delicate open reticulum, chiefly confined to their top edges, below 

 which they appear membranous and very porous. Though the tops of the walls are reticular 

 no radial structures can be traced across this reticulum (fig. 7), not even in the shallower 

 calicles at the sides. Within the fossa, however, and below the margin, 24 septal ridges, or 

 rows of short exquisitely fine points, run down the walls. From what appear to be the 

 primaries thin irregularly radial paliform plates rise up, but do not reach to the top of the 

 wall, except in small intercalicular buds. The secondaries (?) are merely rows of long thin 

 spikes, often bent so as to fuse with the primaries. The tertiaries are minute hair-like 

 points, set with broad bases on the wall. The septal formula is obscured. There is often 

 a central tubercle, which in the deep calicles is a medium directive plate. Owing to the 

 rudimentary conditions of the tertiaries the interseptal loculi are conspicuous. 



"In the vertical section a striking contrast can be seen between the stout vertical and 

 the horizontal elements of the skeleton. Tabulae are very numerous. 



"The peculiarities of this coral are: (i) the "pulvinate" growth; (2) the neatly 

 circular calicles; (3) the fact that the top edges of the walls are reticular, even though 

 they appear below the edge to remain simple and membranous; (4) the nearly laminate 

 primaries, with their conspicuous but thin paliform plates, which rise to within 1.5 mm. of 

 the mouth of the calicle, except in the shallow lateral calicles and in young buds; (5) the 

 spike-like secondaries and tertiaries, the latter being very minute. 



' 'There is one specimen, an almost symmetrical oval mass, about 9 cm. in long diameter. 

 It is infested with calcareous worms, whose tubes coil among the calicles, and mostly open 

 without bending up free of the surface. For other specimens, showing the same neatly 

 punctured cylindrical calicles and the star-like arrangement of pali, see Table IV, p. 180. 

 They all differ in important points, in depth and size of calices, in the thickness of the walls, 

 in the character of the pali, in method of growth. 



"a. Zool. Dept. 86, 12.9. 304. 



"See pp. 67, 68, 69 for other specimens from Zamboanga, which Mr. Quelch classed 

 under the same name with this coral." 



According to Bernard the wall in G. tenuidens is not as in these specimens, but 

 his figure (plate 4, fig. 7) does not bear out his statement, as it clearly indicated 

 radial (costal) elements in the wall. 



Bernard's scheme of reference to specimen is so peculiar that it is scarcely 

 worth while to try to match other specimens with his descriptions and figures. It 

 is probable that his Goniopora Great Barrier Reef (12)4 and (15)5 belong to this 

 species. 



Rhodarcea tenuidens as cited by Bedot from Amboina is, I believe, correctly 

 identified. 



Distribution. — Great Barrier Reef; Amboina (Quelch, Bedot); off Zamboanga, 



Philippines (Quelch). 



Genus PORITES Link. 



1807. Porites Link, Beschreib. Nanir. Samml. Rostock, p. 162. 



1901. Porilfs Vauglian, Samml. Geol. Reiclis Mus. Leiden, ser. 2, voL 2, p. 73. 



1901. Porites Vaiighan, U. S. Commission of Fish and Fisheries Bull, for 1900, vol. 2, p. 314, plate 28. 



1902. Porites Vaughan, Proc. Biol. Sue. Wash., vol 15, p. 56. 



1905. Poriifs Bernard, Porites of the Indo-Pacific Region, pp. 303, 35 plates. 



1906. Poritis Bernard, Porites of the Atlantic and West Indies, pp. 144, 17 plates. 



Type species : Madrepora porites Pallas'. 



'For an account of the restriction of this name, see references to Vaughan's papers cited in the synonymy. 



