58 RECENT MAURE1'..H.\KIA OK THE H.XW.MIAN ISLANDS AND LAYSAN. 



uM.ul riitlir...- awav of tin- septa near tlio calicL.lar Mua<-in." The remarks made 

 u.uler tvpi.al rnronhmm slu.w that the e.Keavation of the septal margins n.ar tlie 

 calieular edge is a common individual variation; eon.se.iuently this criterion lapses. 

 There is also variation ii. the density of the corallum. F. pateu>< and F. mistral,' of 

 Moseley tlierefore are not only synonyms of F. pavonimnn, but are synonymous 

 with the variety dutincttun. 



Dunean-s Hgurcs of F. dl^indmn. (l.sTS) showed tluit it could be .separated 

 specitically from F. pavonhnnn neither by the angle between the lateral edge nor by 

 the septa having '24 instead of 48 princii)als, l)ut h.> did not connect the two. Alcock 

 evidently suspected that they probably should be united, judging from several 

 remarks, (lardiner delinitely vmited them. The specimens obtained Ijy the JM«- 

 tross, 1902, give additional coiitirmation to Gardiner's conclusion. 



I think, howev(M-, that dlstlnctuii, can be ii.sed advantageously as a varietal name 

 under pavommai,. and would define it as follows: Angle of divergence of lateral 

 edges less than 135-, the edges u.sually with .rests: the greater diameter of the calice 

 exceeds the height of the corallum. 



Three specimens obtained by the Alhutrosx are referred to this variety, and 

 from theui Tal)le W has been ])repared. 



Table IV. 



«Meu.sured e.xi'lusive of the crests. ^ Figured. 



Specimen .No. !.'<> of this table is nearest to s])ecimen No. liii of Table II. No. L'li 

 is actually smaller, and besides that it has undergone rejuvenescence. The new wall 

 at one end of the calice is '2.^> mm. within the old; at the other end the newer wall 

 is closer to the older; on the median portions of the faces the growth is continuous. 

 This rejuvenescence succeeded a contraction of the calice, brought about by some 

 unknown cause. The angles of divergenct^ of the lateral edges and of the faces are 

 not greatly diti'erent in the two specimens. The lateral edges in No. 26 bear well- 

 developed crests, whereas in No. 22 they are weak. Specimen No. 2p stands between 

 No. 2t> and No. 27. The last is the most compressed specimen examined and com- 

 pared with the other .si)ecimens is relatively heavy, the Imsal portion apparently 

 having been tilled, ])artially at least, with stereoplasm. In these specimens the 

 excavated zone around the upper .septal margins i.s absent or only faintly developed. 



Localities. — Previously reported from Japan (Milne Edwards and Haime): 

 Porcupine expedition (Duncan); 3!H 8.5' N., 9- 56' AV.. depth 994 fathoms, tempera- 

 ture 40.3- F.; 36 M4' N., 8- 8' W., depth 364 fathoms, temperature 52.7° F.; 36= 29' 



