578 



Foslie and Howe : New coralline algae 



(M. A. Howe, 3 March 



1906, no. 4224). 



ypetum 



thon frutescens Fosl. f. flabelliformis, of the South Pacific, originally 

 described * from Funafuti, but is evidently quite distinct from that 

 species, being coarser, f more anastomosed, often much more 

 widely dilated, and more conspicuously decutescent ; the con- 

 ceptacles of sporangia are somewhat larger (about 1 mm. diameter 

 vs. 500-600 fi in G. frutescens) and are rather less abruptly conical, 

 and the sporangia attain larger dimensions (reaching maxima of 



168 fx in length and 102 [i in width vs. Iio/i and 



50/^ 



in G. 



frutescens) ; the perithallic layer is thicker, and after decalcification 



1 



the cells of both perithallium and medullary hypothallium appear 



more rounded at the angles and firmer-walled than in G. frutescens. 



Conditions of Goniolithon acropctunt with subterete branches 



sometimes bear a slight resemblance to forms of G. strictum Fosl., 



.b 



Figure 1. Goniolithon acropetum ; a, end of a terete branch showing tetra- 

 sporangial conceptacle and exfoliations, X 5 \ b, tetraspores, X I 5°« 



but are coarser, less fragile, and have less tapering branches. A 

 small form of G. strictum was found growing within half a mile of 



ipituni 



ipetwh 



flabelliform branches have a certain superficial resemblance to 



Litliopliyllum 

 Litlwphyllum 



platyph) 



n Fosl. (St. Martin, West Indies) and 

 pseudodentatum Fosl. & Howe (Porto 



ty 



Both 



of the last named forms are either not at all decutescent or flake 

 off only minute and irregular scales. 



* Det Kg]. Norske Videnskabers Selskabs Skrifter. No. I. 1900. 

 t Compare published photographs of G. frutescens f. typica, in The Fauna and 

 Geography of the Maldiveand Laccadive Archipelagoes 1 : pi: 25. /. 4 ; and in Coral- 

 inaceae Siboga-Exped. />/. /o. /. 7-9. 1904. 



