282 



MH. A. W. WATERS OX 



' Challenger ' Eeport. A * Challenger ' specimen from Tristan da 

 Cunhawas submitted to me named L. Jimbriata. This is L. eclii- 

 nata with an ovicell, so that the VLSime Jimbriata must be dropped 



The ovicells sometimes occur as inflations over the central area, 

 as in L. grignonensis, B. (see Ann. Mag. Nat. Hist. ser. 5, vol. 

 XX. pi. vii. fig. 4), L. novcB-zelandice, B.,X. wanganuiensis, Waters 

 (Quart. Journ. Geol. Soc. vol. xliii. p. 346), L. Holdsworthii, B., 

 L. echinata, B. ; or it may be nearer to the edge, showing the 

 ovicellular ducts as figured by Mr. Hincks mLicJienopora radiata. 



Although now keenly on the look-out for ovicells, it is a very 

 difficult study, which can progress but slowly and only be done 

 satisfactorily with ample material collected from a few localities, 

 and one cannot help feeling despair when trying to determine 

 the Liclienoporw ; but it is a genus which, when understood, is 

 perhaps more likely than any other to throw light upon the 

 Cyclostomata generally and upon some fossil forms. 



LiCHENOPORA CALIFOENICA, Buslc. (PI. XV. fig. 1.) 



Unicavea californica, d'Orb. Pal. Frang. p. .972. 



Discoporella californica. Busk, Cat. Mar. Poly. pt. iii. p. 32, pi. xxx. fig. 5. 



Specimens from Port Western (Victoria) given to me by Miss 

 Jelly seem to be the species described by Mr. Busk ; but as 

 d'Orbigny's description might apply equally well to three or four 

 species, it seems preferable to consider Mr. Busk as the author. 



The radii are usually bi- or triserial, though in parts only uni- 

 serial, and in one specimen most of the rays are uniserial and only 

 locally biserial ; the interserial spaces have round or angular cells, 

 but when these interserial cancelli are examined at a level below 

 the surface they are usually seen to be round. The mouths of the 

 cells are prolonged on the distal margin, namely, the side nearest 

 to the border of the zoariuin. Zooecial tube about 0*06 mm. 

 wide inside. When the ovicellular cover is removed the central 

 area is seen to have large reticulated spaces. The upper part of 

 the ovicell is formed by a finely perforated plate extending between 

 the rays like the cogs of a wheel. There is a thick calcareous 

 rim at the border of this area. 



The thin calcareous border of the zoarium is not shown, as this 

 is very variable in size, and probably of no specific value. 



Loc. California {Busk); Port Western (Victoria). 



LiCHENOPORA ECHINATA, MacO. (PI. XV. figs. 2, 8,6.) 

 Discoporella echinata, MacG. Trans. Hoy. Soc. Vict. vol. xx. p. 12/, 

 fig. 4. 



