(131) 
those provided with branches resemble young attached specimens 
of G. strictum, though the crust when present in the latter seems 
usually thinner than in G. RAzzophorae and shows some differences 
in structure. 
Goniolithon strictum nanum var. nov. 
eka a crowded, subfastigiate, terete or subcompressed, 0.8- 
iameter, mostly 5- 10 mm. high: otherwise as in typical 
Conplithon strictum Fosl. (PLATE 82, F 
Porto Rico: San Juan, mostly in shallow tide-pools (zo. 2275). 
This delicate form corresponds to Gontolithon frutescens subtile 
Fosl. (Siboga-Exped. Monog. 61: 53. Al. zo. f. 12, 73) and is 
possibly identical with it, as it is not altogether certain that the 
Atlantic G. strictum can be kept separate from the Pacific G. 
frutescens. 
Goniolithon accretum sp. nov. 
Thallus light-rose when living, or, when growing in exposed 
places, commonly decolorate or very light rose-gray or sometimes 
of a slightly yellowish slate-color, forming thin crusts of indefinite 
cally elongated and ee 1oy in length, sometimes wits the 
longer diameter horizontal; heterocysts 20-25 # long: conceptacles 
(of sporangia?) about 300-400 # in diameter. (PLATE 85, F. 2; 
P 
exposed surf-beaten rocks or sometimes on pebbles in more 
protected places 
Fiorina: Sands Key (0. 29204, type). 
Bauamas: Great Sturrups Cay (os. 7627 and 37629) ; probably 
also zo. 3295 from Dollar Harbor, South Cat Cay 
Nos. 1994 (p.p.) and 2794, from Santurce (San Juan), Porto 
Rico, are possibly to be referred to the same species. 
he specimens seen are mostly sterile and the species is perhaps 
not a well-defined one. It stands near Gonzolithon Notaristz 
(Duf.) Fosl. but diverges in the apparently smaller and less promi- 
nent conceptacles and more especially in the smaller and frequently 
thinner-walled perithallic cells. The cells sometimes even remind 
one of those of Lithophyllum decipiens Fos). 
