1888.] NATURAL SCIENCES OF PHILADELPHIA. 307 



corallum is thus openly turbinate, or even pediculate, and exhibits 

 in regularly scalariform outline the successive stages of outward 

 development. 



Diploria cerebriformis, Lamk. 



This species is exceedingly abundant in the shoals lying to the 

 leeward of the marginal reef, where its huge hemisi^herical or reni- 

 form masses of bright orange, measuring as much as four or five 

 feet in diameter, can be distinctly seen through the transparent 

 waters at depths of from six to fifteen or twenty feet. I cannot say 

 how much farther down the species extends. It is equally abundant 

 in Castle Harbor, where it is largely instrumental in building out 

 the shore-platform which, at a moderate distance from the shore, 

 descends vertically into deeper water. When attached by a con- 

 tracted base, the brain-coral may be readily removed from its moor- 

 ings; but where the base is largely co-extensive with the under-surface 

 of the corallum the difficulties of removal are very great, neces- 

 sitating much undercutting with a chisel. The largest specimen 

 obtained by us measured about 28 inches across ; our efforts to 

 dislodge a specimen about four feet in diameter proved unsuccessful. 



Diploria Stokesi, Edwards and Haime. 



We obtained a number of specimens of this species in Castle 

 Harbor and through presentation ; for the latter my thanks are due 

 to Miss A. Peuiston, of Penistons. The habitat of the species, as 

 far as I am aware, had not hitherto been noted. Edwards and 

 Haime in their description of the species (Hist. Nat. des Coralliaires, 

 II, p. 403, pi. T>, fig. 3) state " Patrie inconnue. " I believe it may 

 be assumed that this species is the form described and figured by 

 Knorr as 3fadrepora labyrinthiformis (Delicice Natures. Selectee, I, p. 

 18, PI. A 4, fig. 1). In our collections we have a closely related, 

 and possibly identical species, which assumes a ring form, and in 

 which the peculiar calycular hollows of D. Stokesi run out into 

 parallel transverse grooves on the inner side of the ring. 



ALCYONARIA. 



The gorgonians are abundant in the waters inside of the bounding 

 reef, whence nearly all our specimens were obtained. A few were 

 nipped up on the south side of Castle Harbor, and at the passage way 

 conducting from the north into that body of water. 



