86 PAPERS FROM THE DEPARTMENT OF MARINE BIOLOGY. 



Habitat, etc., Cocos-Keeling Islands. — A note by Dr. Wood Jones states: "Bar- 

 rier coral, in rough, clear water; colonies not very large; color greenish or yellowish." 

 Distribution. — Indian Ocean, Seychelles to Cocos-Keehng; Australia; and per- 

 haps Vanikoro (see Matthai, op. cit., for distribution). 



.A .^ 

 Orbicella gravieri, new name. 



1907. Orbicella annuligera Vaughan, Proc. U. S. Nat. Miis., vol. 32, pp. 252-253, plate 20, fig. 3; plate 



21; plate 22, fig. 4, (non Astrea annuligera Milne Edwards and Haime, 1849). 

 191 1. Orbicella annuligera Gravier, Ann. L'Inst. Oceanogr., vol. 2, fasc. 3, p. 57. 



The description and figures which I have published should be adequate for 

 the identification of the species. ^A/rA .5i'^bO) 



Locality. — Djibouti, French Somaliland. 



Orbicella curta Dana. 



Plate 28, figures 2, 3, Dana's cotypes of 0. curia; figures 4, 4U, one of Dana's cotypes of 0. coronata; figure J, 

 specimen from Murray Island. Also plate 17, figure 32, of Dr. Mayer's article. 



1846. A. Orbicella curta Dana, U. S. Expl. E.xped., Zooph., p. 209, plate 10, figs. 3, 30-31-. 



1846. J. Orbicella coronata Dana, U. S. Expl. Exped., Zooph., p. 211, plate 10, figs. 4, 4a, ,^b. 



1899. Orbicella tvakayana Gardiner, Proc. Zoul. Soc. London for 1899, p. 753, plate 49, fig. 2. 



1914. Favia tvakayana (and synonymy) Matthai, Trans. Linn. Soc, 2d ser., Zool., p. 104, plate 25, fig. 4. 



The identification is based on Dana's original specimens of J. Orbicella curta 

 (Nos. 14 and 22, U. S. Nat. Mus.) and his cotypes of A. Orbicella coronata (Nos. 

 57, 58, U. S. Nat. Mus.). Although the two specimens of 0. curta are originals of 

 Dana, at least a part of his description is based on another specimen, as none of 

 the septa in these is hollow. Matthai's description of the species is good, but 

 applies more precisely to Dana's coronata than to curta; however, the variation 

 on the original specimen oi coronata shows that the greater exsertness of the margins 

 of some of the principal septa is not of specific value. The calices of coronata on 

 parts of the corallum are somewhat larger and more deformed than in curta, but 

 in these characters there is overlapping. Diameter of fully grown caUces in 0. 

 curta, 4.5 to 5.5 mm., in 0. coronata, from 4.5 mm. up to 8 by 6 mm. in a large 

 deformed calice. Reproduction normally by budding between the calices, but 

 there is occasional fission. 



There are in the U. S. National Museum specimens of this species from the 

 following localities: 



Fiji Islands, Dana's originals of 0. curta [i specimens); 



Wake Island, an original specimen of 0. coronata Dana; 



Tahiti, Dana's original of 0. coronata (i specimen); 



Tahiti, Flint Island (C. G. Abbot, collector); 



Paumotus, Fakarawa {Albatross, 1899-1900), (11 specimens); 



Paumotus, Hereheretue {Albatross, 1899-1900), (2 specimens); 



Probably Paumotus {Albatross, 1899-1900), (2 specimens). 



The more usual facies of the Paumotuan specimens is that of 0. coronata, 

 as elliptical calices are common, but the typical 0. curta is also represented. 



The single specimen obtained by Dr. Mayer at Murray Island evidently was 

 growing under adverse conditions, as a part of the colony had been killed. The 

 living corallites have somewhat thicker skeletal structures than is usual in the 

 species, a kind of variation frequent in corals living in an unfavorable environment. 

 The largest calice is nearly 6 mm. in diameter. Calices crowded, from less than i 

 to about 2 mm. apart. Costae thick, equal, with coarse, transversely compressed 

 granulations. 



