1899.] ASTR^lD COBALS PROM THE SOTTTH PACIFIC, 747 



1. GoniastkjBA eximia Dana. 



Astrcea eximia, Dana, Zooph. p. 242, pi. xiii. fig. 4 (1848). 



Goniastrcea eximia, Milne-Edwards & Haime, Cor. ii. p. 448 

 (1857). 



The corallum of this species forms large irregularly-convex 

 masses, which have thin spreading edges, covered underneath by a 

 well-developed epitheca. 



Three orders of septa are complete, and the fourth neai'ly so. 

 Of these, two orders typically have pali, forming a well-marked 

 crown round the axial fossa. The number of pali, however, varies 

 greatly, in some colonies averaging in the larger calices 10-11, and 

 in others 12-13. Some, too, of the tertiary septa in the largest 

 calices project to the axial fossa, and have distinct paliform lobes. 

 There is a true, finely trabeculate columella, about 1 mm. broad, 

 situated about 2 mm. below the pali, which themselves are about 

 1 mm. below the edge of the calice. 



The larger calices are 3-4-5 mm. in diameter. The walls are 

 very thin, formed by two completely-fused thecse. The septa are 

 scarcely exsert, and are not generally continuous from calice to 

 calice. Usually the primary septa in one calice lie opposite to the 

 tertiary or quaternary septa in a neighbouring calice, not opposite 

 to primary or secondary septa. 



Rotuma ; reef, three specimens. Wakaya, Fiji ; reef, two 

 specimens. 



2. GoNiASTE^A solida Blaiuville. 



Dipsastrcea solida, Blainville, Diet. t. Ix. p. 338 (1830). 



Goniastrcea solida, Milne-Edwards & Haime, Cor. ii. p. 444 

 (1857). 



A single small specimen from the E-otuma reef, conforming 

 closely to the above descriptions. 



G-enus AsTEiEA. 



Astrea, Lamarck, Syst. des Anim. s. Vert. p. 371 (1801). 



Astrcea, Dana, Zooph. p. 200 (1848). 



Favia, Milne-Edwards & Haime, Cor. ii. p. 426 (1857). 



Astrcm, Quelch,' Challenger 'Eeport on Eeef Corals, p. 96 (1886). 



Corals of this genus were among the most abundant found both 

 at Funafuti and Eotuma. They do not occur generally near the 

 rim of a reef, where it is exposed to the open sea, but are often 

 found on the reef-flat behind. Their favourite position, however, 

 is on shoals — preferably near a passage — in the comparatively 

 quiet water of the lagoon. 



Milne-Edwards and Haime enumerate 44 species of the genus. 

 Of these species Dana's descriptions are by far the best, as the 

 main characters on which the species are based are always indicated 

 and figures of all are given. Valenciennes's MSS. descriptions 

 are absolutely useless; and many of the species described by 



