64 bulletin: museum of comparative zoology. 



margins is variable, ranging from 1 mm., or even less, to 5 mm. At and just below 

 the calicular margins are costae corresponding to the primary and secondary septa, 

 they usually are not continued far down the outside of the corallite wall. 



The coenenchyma is highly developed, absolutely solid, its surface striate, or 

 checkered by superficial canals. 



Septa in three complete cycles, the primaries are exsert between .5 and 1 mm., 

 the secondaries less prominent, the tertiaries with scarcely elevated margins. The 

 inner margins descend abruptly, those of the first two cycles extend to the axis, and 

 may or may not form a weak, false columella. The septal faces are striate and 

 granulate, septal edges entire. 



The corallite cavities are solidly filled below by stereoplasm. 



Locality : — Station 4642, southeast face of the Gralapagos Islands, 5 miles 

 from southeast end of Hood Island ; depth, 300 fms ; bottom, broken shells 

 and Globigerina ; temperature of the bottom, 48.6° F. 



Remarks : — This species belongs near Madrepora oailata (Linnd) but differs in 

 its shorter, relatively thicker branches, and its more prominent and deeper 

 calices. 



Pocillopora cespitosa Dana var. 



Plate 3, figs. 1-lb. 



1846. Pocillopora cespitosa Dana, Zooph. Wilkes Expl. Exped., p. 525, plate 49, 



figs. 5, 5a. 



1846. Pocillopora brevicornis (pars) Dana, Zooph. "Wilkes Expl. Exped., p. 526. 



1860. Pocillopora cespitosa Milne Edwards, Hist. nat. Corall., 3, p. 303. 



1869. Pocillopora caespitosa Verrill, Proc. Essex Inst., 6, p. 91. 



1886. Pocillopora cespitosa Quelch, Reef Corals, " Challenger " Rept., p. 66. 



1901. Pocillopora caespitosa Studer, Zool. Jahrb. Syst., 40, p. 399. 



One specimen was obtained. It is a clump 8 cm. tall, 10.5 cm. long, 

 and about 8.8 cm. wide. It is composed of rather crowded, compressed 

 branches, that bear verruciform brauchlets. In form it resembles 

 the stylophoroid variety of the species found in the Hawaiian Islands. 

 The septa and columella are distinct, especially on the basal portion of 

 the corallum, where the latter is often styliform. 



For a description of the variations of this species, my report on the 

 Hawaiian Madreporaria, U. S. Bureau of Fisheries Bulletin, should be 

 consulted. 



Locality : — Motus reef flats, Manga Reva, Paumotus. 



