CORALS FROM MURRAY, COCOS-KEELING, AND FANNING ISLANDS. 77 



Pocillopora danse Verrill. 



Plate 22, figures i, la, specimen from Murray Island; figure 2, part of Verrill's type. 



1846. Pocillopora favosa (pars) Dana, LI. S. Expl. Exped., Zooph., p. 528, plate 50, fig. I [non Lhrenberg). 

 1864. Pocillopora danieVeinW, Bull. Mus. Comp. Zool., vol. I, p. 59. 

 1869. Pocillopora dana Verrill, Proc. Essex Inst., vol. 6, p. 93. 



The type of Verrill's P. dance is in the U. S. National Museum, No. 696. 

 Verrill's description in 1869 is good. 



The following is a description of the Murray Island specimen: 



Corallum forming bushy clumps, exceeding 18 cm. in height. Some main stems may 

 be more or less prolate, and bear secondary, taller branches on the upper surfaces with 

 shorter branches on the sides. All branches undergo subdivision. Cross-section of branches 

 subterete. Diameter of branchlets below terminal bifurcation, 12.5 by 14 mm. Ends of 

 branchlets usually compressed, one 7 by 17 mm. in diameter, excluding verrucae; all inter- 

 gradations tosubteretewith adiameterof only 7 mm. Distance between terminalsof branch- 

 lets, measured between opposed verrucae, 8 to 18 mm. 



Verrucae over terminals and on sides of branchlets and branches. Those on terminals 

 usually compressed in planes transverse to plane of compression of branchlets, and some- 

 what swollen near the upper end. Diameters 3 by 5 mm., 4 by 6 mm., 5 by 6 mm.; height, 

 up to 5 mm. or slightly more; distance apart, up to 5 mm. Lateral verruca, inclined toward 

 end of branchlets or branches, up to 5 or 6 mm. in basal diameter, ends rounded. Low down 

 on stems they are scattered and form low-domed protuberants up to 6 mm. in diameter. 



Calice 1.5 mm. in diameter on terminals; 0.75 mm. in diameter on old portions of 

 corallum. Intervening walls thin on and near terminals; thicker on older portions of coral- 

 lum, up to 0.75 mm., 0.3 to 0.5 mm. frequent; depth about 0.5 mm. Coenenchyma compact; 

 surface granulate, granules usually blunt, a circle of about 16 around each calice; there may 

 be one or two intervening rows or circles dependmg on distance apart of the calices. Septa 

 represented by spines, not lamellate, usually distinct, even on verrucal summits, well devel- 

 oped near bases of branches; 12 the usual number, plane of symmetry distinct, composed 

 of vertically arranged trabeculae, projecting inward as spines from the wall. No definite 

 columella; bottom of calice granulate. 



Station, Murray Island. — South reef; outer edge of reef in a strong tidal cur- 

 rent; almost awash at low tide, and subject to strong seas. 



The Murray Island specimen differs from Verrill's type in that there are 

 elongate main branches along the sides of which are lateral branches, and in that 

 the verrucse are somewhat larger and more tumid. But the calicular, including 

 the septal, characters are identical, and the verrucae are similar in form and arrange- 

 ment. The differences, therefore, are probably of vegetative origin. There is 

 resemblance to some of the outer fronds of P. squarrosa Dana, on the lower parts 

 of which are low-domed verrucae about 6 mm. in diameter; and also to P. meandrina 

 var. tvberosa Verrill.^ 



Distribution. — Murray Island, Australia; Philippine Islands, without definite 

 locality label, a specimen almost a duplicate of the one from Murray Island; Fiji 

 Islands (Verrill's type). 



Pocillopora verrucosa (Ellis and Solander) Lamarck. 



Plate 23, figure I, part of specimen so identified by Dana, No. 695, V. S. Nat. Mus.; figures 2, la, branch of a 



specimen from Cocos-Keeling Islands. 



1846. Pocillopora verrucosa Dana, U. S. Expl. Exped., Zooph., p. 529, plate 50, figs. 3, 3a. 

 i860. Pocillopora verrucosa Milne Edwards, Hist. nat. Corall., vol. 3, p. 305. 



Milne Edwards doubted Dana's identification of this species, but it seems to 

 me that they were dealing with the same species. Two of Dana's specimens are 



'See Vaughan, U. S. Nat. Mus. Bull. 59, pp. 99-100, 1907. 



