180 



DEPARTMETfT OF THE NAVAL SERVICE 

 Genus Schizotricha. 



Trophosome. Colony simple, branched, with hydrocladia pinnately arranged. 

 Gonosome. Gonangia springing from the stem, branch or hydrocladium, not 

 directly protected. 



Schizotricha gracillima (G. O. Sars). 



Trophosome. Stem fa'scicled, sparingly branched; 

 branches fascicled proximally; each hydrocladium, one 

 to an internode, usually branched dichotomously, one, 

 two or three times ; few intermediate internodes ; hydro- 

 thecae small, cup-shaped, about as wide as deep; nema- 

 tophores large, a supracalycine pair, three or four 

 mesial on each internode, one in the axil of each hydro- 

 cladium and others .scattered over the stem. (From 

 Nutting's description.) 



Gonosome. " Gonangia borne in pairs on the stem 

 near the axils of the hydrocladia, and also at the fork- 

 ings of the latter; they are cylindrical in shape, taper- 

 ing at the proximal end and almost sessile, the pedicel 

 being much reduced'' (Nutting). 



No. 1( 

 Schizotricha gracillima 

 (after Nutting). 



Genus TuEcocARrus. 



Trophosome. Stem fascicled; hydrotheca? with one or two large, anterior teeth, 

 the others small. 



' Gonosome. Corbuluc composed of widely separate leaves, each bearing a hydro- 

 theca near its base. 



Thecocarpus myriophyllum (Linnaeus). 



Trophosome. Stem fascicled, swollen at intervals, 

 but slightly branched; hydrocladia alternate, closely 

 approximated; hydrotheca; deep, cylindrical, with one 

 large anterior tooth ; supracalycine and mesial nemato- 

 phores small ; cauline nematophores numerous but small. 



Gonosome. Corbulae open, some distance from the 

 stem, each with a hydrotheca near its base and a row 

 of nematophores along its distal leaflet. 



No. 109. 

 Thecocarpus myriophyllum. 



