394 



filaments are sometimes issued from the gland-cells too (Fig. 

 375 b}. 



Only tetrasporic plants occurred. The tetrasporangia are 

 developed in the cortical layer (Fig. 376 D}. They are cruciately 

 divided and rather small, about 27 jut broad. They occurred in 

 the month of March. 



This species has been found in deep water only (about 12 

 16 fathoms). 



St. Jan: Off Cruz Bay and near Great St. James; off America Hill 

 where it was collected by Dr. TH, MORTENSEN and myself. 

 Geogr. Distrib.: Florida. 



Fig. 377. Chrysymenia planifrons (Melv.) J. Ag. 

 Part of a transverse section of the thallus with tetrasporangia 



(about 80:1). 



2. Chrysymenia planifrons (Melv.) J. Ag. 



J. AGARDH, Epicr. p. 319. 



Chrysymenia Agardhii var. planifrons Melville, Notes on the Alga? of 

 South Carolina and Florida (Journ. of Botany, vol. XIII, 1875, p. 263). 



A fragment of a Chrysymenia with flat thallus is, most pro- 

 bably, referable to this species. It originates from a tetrasporic, 

 and rather old plant. 



A transverse section (Fig. 377) of the thallus bears a close 

 resemblance to that of Chrysymenia Agardhii. In the middle it 

 is more or less hollow and the cavities are more or less filled up 

 with numerous hypha? issued abundantly from the large wall 



