Verrill, Notes on Radiata. 521 



only by thin walls. Septa twelve, usually very narrow or rudimen- 

 tary, the lower part generally more developed than the upper ; some- 

 times one is broader and joins the very small columella, which is, 

 however, generally wanting. 



The largest specimens seen are more than a foot in diameter ; the 

 branches "5 to 1 inch ; verruca? '30 of an inch long ; "10 to 20 in di- 

 ameter ; cells 'OS to '04 in diameter. 



Acapulco, — A. Agassiz ; Socorro Islands, — J. Xantus; Pearl Islands, 

 — F. H. Bradley ; La Paz, — J. Pedersen. 



Pocillipora capitata, var. porosa Verriii. 



Pocillipora capitata, var. porosa Verrill, Proc. Essex Inst, vi, p. 99, 1869. 



Coralla forming large rounded clumps, 10 to 15 inches in diameter, 

 with more or less elongated, divergent or crowded, angular, and often 

 flattened branches, which are usually '25 to -35 of an inch in thickness ; 

 •50 to "75 in breadth ; and 1 to 3 long, often truncate or digitately 

 lobed at the end. VerrucjB variable, mostly ascending, often large 

 and prominent, generally elongated, roundish, tapering to the sub- 

 acute end, the upper ones often appressed, obsolete on the summits of 

 the branches, where the cells are closely crowded. Cells large and 

 deep, the lateral ones mostly crowded, the intervening spaces gene- 

 rally less than their diameters, often not half as much. Septa 12 or 

 24, distinct, nearly equal, narrow, slightly exsert and acute at summit. 

 Surface of the ccenenchyma, between the cells, finely spinulose, the 

 spinose grains often crowded, but frequently forming only a single 

 row. The cells are but little closed up in the interior by solid deposits 

 and the texture of the coral is, therefore, quite porous. In one large 

 specimen the branches on one side are of the normal size and form, 

 while on the other they become more slender and much subdivided 

 at the ends into small, obtuse, lobe-like or digitate branchlets. The 

 cells on this part are smaller and more distant. 



The larger specimens are about 10 inches high and 12 broad; the 

 larger branches "50 to 1 inch in width ; -25 to "35 in thickness ; cells 

 •04 to "05 of an inch in diameter. 



Near La Paz, brought up by divers, — J. Pedersen. 



The Museum of Yale College possesses four large and several small 

 specimens of this form. 



Pocillipora capitata, var. robusta Verriii, nov. 



Coralla forming large, more or less hemispherical, close clumps of 

 stout, angular, mostly flattened, obtuse, dichotomous branches, Avhich 

 usually fork at distances of from 1*5 to 4 inches, in large specimens. 



