A. E. Verrill — Bermudian and West Indian Reef Corals. 163 



of dead rounded corals (Mmandra conferta in one ease), but they 

 show no trace of branching. 



The calicles are unusually small and shallow, nearly uniform in 

 size, mostly closely crowded, polygonal, and separated by thin 

 fenestrated walls. The septa are 12 narrow, thin, roughly echino- 

 lacerate and fenestrated, often a little exsert ; their inner edges unite 

 to a wide columelliform ring, leaving a circle of very small loculi ; 

 in the center of the ring-like columella there is a small pit. The 

 pali are very slender, erect, lacerate, mostly 3 to 5, sometimes 6 ; 

 frequently all are absent or broken off. 



The whole surface of the coral has a delicate, lace-like appearance, 

 owing to the uniformly small size of the calicles and the thinness 

 and porosity of the walls. 



The masses are 3 to 5 inches in diameter ; breadth of the calicles 

 0.9 to 1.2 mm , mostly about l mm ; when in rows there may be 9 to a 

 centimeter. 



Parahyba do Norte and Pernambuco, Brazil, — R. Rathbun. Our 

 specimens are from Pernambuco, — coll. C. F. Hartt. No. 4552. 



, Mr. Vaughan suggested that this might be a young stage of 

 1\ clavaria. To me they seem to be perfectly distinct. 



Family Acroporidae Ver., nom. nov. 



Madreporidce Dana, Zooph., p. 431, 1846. 



Madreporidce (pars) and Poritidce (pars) Edw. and Haime, Corall., iii, pp. 89, 



207, 1860. 

 Madreporidce Verrill, these Trans., i, p. 501, 1867. 



Corals very porous, usually branched or foliaceous, sometimes 

 lobed or massive, encrusting when young, increasing by budding, 

 rarely by fission. Coenenchyma abundant, porous, often spinulose. 

 Corallites cyclindrical, small, generally of two sizes, which may 

 differ in structure. The larger ones may form the terminal or 

 parent calicle of the branches, or occupy only the upper side of 

 foliaceous species. 



Calicles small, deep; septa usually 6 or 12; sometimes more in 

 larger sporadic calicles; usually continuous, but perforated. Dissepi- 

 ments few. Polyps much exsert in expansion ; tentacles slender, 

 tapered, generally 12, rarely more. 



The genus Acropora is the only one in the West Indian fauna, 

 where it has but one species. Montipora and Anacropora are 

 wholly Indo-Pacific; the former has about 100 species. 



