552 A. E. Yerrill — Anthozoa and Hydrozoa of the Bermudas. 



do these colors depend to any great extent on the station, for in 

 some cases all these variations may be found in one place. But 

 those specimens found scattered in shallow water on bottoms of 

 white shell-sand were usually gray, or pale lavender mottled with 

 gray, though the hard parts do not differ from the darker colored 

 ones. One of the commonest forms at Bermuda was named Mvssa 

 fragilis by Dana (Zooph., p. 145, 1846). The type of this, from 

 Bermuda, is still in the Museum of Yale University. This, which is 

 the common more delicate form, should therefore bear the name 

 Isophyllia fragilis. It is possible that the coarser 1. dipsacea (D.) 

 is only a variation of the same species, due to more vigorous growth. 



Quelch also recognized seven species of Oculina from Bermuda, 

 which is doubtless too many, for all the species are variable in form, 

 the degree of elevation of the corallites, etc. Apparentl^^ all the 

 Bermuda forms of Ocidina can be reduced to four species. He also 

 recorded two species of Astrma [A. ananas and A. coarctata). We 

 found these two forms common in tide-pools, but consider them 

 merely variations of one species {A. ananas). 



So, likewise, we consider Diploria Stokesii, listed by Heilprin, as 

 a mere variation of D. cerehriformis, with the ridges wider and 

 more deeply grooved than usual. It is a common form. 



Thus, at least eight nominal species should be eliminated from 

 Quelch's list, leaving but 15 species. On the other hand he omitted 

 one of the commonest species [Porites astrmoides), recorded in other 

 lists,* and Siderastrma radians^ recorded by Jones. I have now to 

 add three additional species of true reef corals, two of which [Orbi- 

 cella annularis and O. cavernosa) are not uncommon and grow to 

 large sizes. Thus the number of true anthozoan corals now known 

 is about 20. 



All these corals, except the Plesiastrcea, herein described as new, 

 are common West Indian and Florida species. The coral-fauna of 

 Bermuda differs chiefly from that of the Florida reefs and the 

 Bahamas in the absence of certain prominent and well known genera 

 and species characteristic of the latter, especially the genera Madre- 

 2)ora, Manicina., ColpophylUa, Eusniilia, Dichocoenia, Dendrogyra, 

 Gladocora, and the two very common species, 3IcBandrina clivosa 

 and Agaricia agaricites. Possibly some of these may yet be dis- 

 covered at Bermuda, but if found there at all they must be very 

 local and rare, for the Bermuda corals have been extensively col- 

 lected. 



* See Richard Ratlibim, Proc. U. S. Nat. Mus., 18S7, p. 354. 



