18 FOLKE FOLKESON, MADREPORARIA. 



distinctly radiating, in Polyphyllia tliose of the central calices are subra diating, the rest 

 not at all radiating, and in Lithactinia there are no radiating septa and no axial furrow; 

 moreover in Lithactinia the corallum forms a plate, more or less plicate. With good reason, 

 Gardiner (15, p. 260) unites the three genera under the common name of Polyphyllia 

 and recognizes (1. c., p. 287) orily two species of that genus, viz. P. talpina (Lamarck 

 1801) and P. novae-hiberniae (Lesson 1833). 1 To these two species I now add a third, 

 which may be a variety of P. talpina (Lamarck) only, but is distinguished from 

 the typical forms by the characteristic shape, the very marked axial calices, and the 

 very dense appearance of the corallum. 



In the Swedish State Museum there are preserved 8 specimens (including that 

 of Dr. Mj Öberg" s collection) of the genus Polyphyllia; two of them belong to P. 

 novae-hiberniae (Lesson). 



The measurements in cm of the six others are as follows: 



No. Length of corallum Greatest 



— 

 along the along the middle line breadth distance between height of 



axial fossa of the horizontal plana 

 between the margins 



1 



55,7 



43,9 



15,5 



2 



30 



27,8 



7,3 



3 



20,3 



18,4 



7,2 



4 



20 



17,8 



5,3 



5 



35,2 



23,8 



4,4 



6 



30 



28 



3,2 



the margins corallum 



14,4 10 



6,3 4,0 



7 2,6 



4.5 2,8 

 2 4,2 



2.6 2 



Nos. 2 — 5 from Java; no. 1 locality not recorded; no. 6 from Australia (Dr. Mjö- 

 berg's specimen). 



Fam. Eiipsamniiidae. 



Leptopsammia columna Folkeson n. sp. (Figs. 28 — 29). 



45 rnilee W.S.W. off Cape Jaubert, 29.5.11, 66 feet, 1 sp. 



From an encrusting base the corallum rises straight to a height of 6,5 mm. Diame- 

 ter in all places 3 mm. 



Septa 24, not exsert över the margin of the wall, almost equal, not fused with one 

 another, growing thinner toAvards the columella, under magnifying power distinctly 

 granulated, very finely denticulate, all very stceply sloping towards the well developed, 

 convex columella, which is of a loose consistency. The calice subcircular with a depth 

 of 1,2 mm. The wall thick: theca porous. Distinct costae are wanting, but there are 

 very finely denticulate, longitudinal keels, here and there broken off or anastomosing, 

 which cannot be seen except under a magnifying glass. Epitheca is lacking. 



» Of this species I publish a photograpli (fig. 27) representing a specimen from Fiji preserved in 

 the Swedish State Museum. 



