522 Verrill, Notes on JRadiata. 



The branches are covered laterally with numerous, rather large, pro- 

 minent, elongated, mostly acute, ascending verrucse, which are pretty 

 evenly scattered over the surface and seldom crowded, rarely obtuse 

 or rounded at the end, usually containing a dozen or more polyp-cells. 

 The verrucse become obsolete at the tips of the branches, which are 

 mostly blunt or truncate and filled with closely crowded, angular 

 polyp-cells. The cells on the sides of the branches and verrucse are 

 rather small, mostly separated by distances about equal to their diam- 

 eter. Septa commonly six, very distinct but narrow, often twelve. 

 Columella either a small papilla or rudimentary and scarcely distinct. 

 Coenenchyma between the cells compact and covered with minute 

 rough granules. In a transverse section the cells are found to be 

 much filled up below, and the coral quite compact ; the transverse 

 dissepiments are rather distant, the spaces between usually exceeding 

 the diameter of the cells. Height of the largest specimens 15 to 18 

 inches ; length of undivided branches 2 to 4 ; breadth '50 to 1*50 ; thick- 

 ness '35 to "75 ; length of average verrucse "30 to '40 ; their diam- 

 eter '20 to '30 ; diameter of cells "02 to '03 of an inch. 



Young specimens attached to shells of Margarltophora fimhriata 

 Dunker, have a few short rising branches in the middle, with a broad, 

 thin, encrusting base. The marginal cells are obliquely appressed to 

 the surface of the shell, their outer edges being flattened and extend- 

 ing, with the septa, which are here conspicuous and like elevated 

 costse, considerably beyond the proper edge of the cells, exactly as in 

 Astrangia and the young of Oculina. The new cells at the edge are 

 also produced by marginal budding, as in the genera named. A study 

 of these marginal cells confirms the affinities of this family with the 

 Oculinacea. 



Gulf of California, south of La Paz, 3 to 6 fathoms, brought up by 

 divers, — J. Pedersen. 



The Museum of Yale College has received upwards of twenty speci- 

 mens of this form, most of them of large size and quite constant in 

 character. But some of the smaller specimens are evidently dwarfed 

 by unfavorable conditions of growth and have very irregular branches, 

 sometimes much divided, and the verrucae nearly obsolete in some 

 parts. The following form, however, seems worthy of a distinct vari- 

 etal name. 



Pocillipora capitata, var. pumila Verrill. 



The coralla consist of elongated clumps of short, mostly obtuse 

 and much divided, crowded branches, arising from the upper side of 



