316 



main axis and screw-formed side-organs. These branches grow out 

 to ordinary branches and contribute to the ramificatoin of the plant. 



The stichidia are found in the ends of the distichously ramified 

 branchlets (Fig. 320). The lowest parts of these branchlets are provided 

 with side-branches as in the case of the sterile ones. In the fertile 

 part, on the other hand, the side branches are normally missing. 

 Each of the four pericentral cells in each segment produces a tetra- 

 sporangium, and is covered with three cells. The tetrasporangia are 

 about 55 LI broad, the whole stichidium about 105 u thick; in the 

 upper end of the stichidium a short vegetative prolongation is often 

 developed ; this consists of several small segments from which short 

 side-branches issue spirally. 



When I wrote above that the stichidia are normally destitute 

 of side-branches, I ought, however, to have pointed out that I have 

 found a few stichidia with well developed monosiphonous, unbranched 

 ramuli placed in a screw (comp. Fig. 320 in which some ramuli are 

 developed in the low r er part of the stichidium). I mention this 

 especially as FALKENBERG always found the stichidia without side- 

 branches and maintained that just this absence of the side-branches 

 makes Mnrrayella only slightly related to the typical Lophothalieds. 



Murrayella peridados was found with tetraspores in the month 

 of January. It occurs in nearly all lagoons and bays where mangroves 

 thrive and it grows near the surface of the sea or a little above. 



This plant was described originally from specimens from St. 

 Croix which HOFMAN BANG presented to C. AGARDH 



St. Croix: Christianssted's Lagoon, Salt River. St. Thomas; Bo- 

 voni Lagoon. St. Jan: Cruz Bay. 



C-eogr. L) 1st rib.: West Indies. Florida, La Guayra. 



Subfam. 8. Dasyeae. 

 Dasya C. Ag. 



1. Dasya pedicellata Ag. 



\',UU>H, C., Systema Alg., 1824, p. 211. COLLINS, F., and A. HERVEY, 

 Algae of Bermuda, p. 136. 



Dasya elegans (Mart.) Ag., Spec. Alg., vol. II, 1828, ]>. 117. KLTZING, 

 Phyc. gener., p. 414. pi. 51, fig. II, Spec. Alg., p. 796. Tab. Phycolog., vol. 

 XIV, tab. 59. HARVEY. Nereis Bor.-Am., part II, p. 60. FALKENBERG, P., 

 Rhodomelaceen, p. 618, pi. 18, figs. 5 17. 



