On THE PlTHOPHORAGE^E. 



59 



crassis et 216 ,u altis, his c:a 70 (i erassis et 164 ft altis; sports terininalibus (noh 

 raro sessilibns) orcuhefonnibus, sursum brevi-acuminatis a pice rotuudato, c:a 93 [t 

 erassis et 232 /.i altis.] 



Locality. Professor P. T. Cleve has found this interesting species in the 

 West-Indies, in the isle of S:t Thomas near Soldier-Bay on humid earth in the 

 shade of bushes. l ) Oct. 1868. — Epiphytically on it grow two undescribed 

 monoecious species of Oedogonium, which it is my intention to describe in 

 another place. 



General Description. Fertile specimens. Caulojid part of the th alius. 

 The ramification of this part is in P. Chvcana nob. somewhat more developed than 

 in t. Ttewensis nob. Most specimens have, it is true, branches only of the l:st 

 degree; but specimens with branches of the 2:d degree are far from being rare, 

 and in a couple of specimens I have seen branches even of the 3:rd degree, but 

 which have almost always consisted of only one sessile spore. The branches of the 

 2:d degree are generally very short. Not seldom those branches consists (like those 

 of the 3:rd degree) barely of one sessile spore; see pi. 4, fig. 13 ss. The principal 

 filament is, when it ends in a spore, often very short, sometimes scarcely 2 mm. 

 long (pi. 2, fig. 13; pi. 4, fig. 16); the branches of the l:st degree in such speci- 

 mens are, it is true, longer, but not very much. Sometimes such little dwarf spe- 

 cimens are quite devoid of branches, and remind one then in a very high degree 

 of a gigantic Oedogonium with ellipsoidic oogonia. The branches are most fre- 

 quently single, but not seldom those of the l:st degree are developed two and two 

 from one cell and are then placed opposite, or almost so, to each other (pi. 2, fig. 

 13; pi. 4, fig. 16; pi. 5, figs. 1 and 2). The normal branches in this species of 

 Pithopltora are placed, as in the others, a small space below the top of the sup- 

 porting cell, which space is most frequently smaller than the diameter of the lowest 

 branch cell, but can now and then be even longer (pi. 5, fig. 2). Cells without 

 branches occur rather seldom, if you do not count the top cells -), the subsporal 

 cells, and the cells belonging to the branches of the highest degree. The lowest 

 one of the cells in the eauloi'd part of the thallus is not seldom devoid of branches 

 (pi. 4, fig. 13 and 16); sometimes, however, this cells carries more branches than 

 the other cells, supporting besides the one or two ordinary terminal branches, 

 an accessorial basal branch (pi. 5, fig. 1 and 6). Accessorial branches, most 

 frequently carrying helicoids, are now and then found even on other cells (pi. 5, 

 fig, 1 at). The comparatively frequent occurrence of helico'ids is particularly re- 

 markable in this species. Most specimens have one or more of these organs. These, 

 generally consisting of the transformed top of a terminal cell, occur in numerous 

 different shapes. Now they are unbranched (pi. 5, fig. 1 h'), now forked, now 



') Among the (Jladophorem two species, viz. Uladophora b'agrceqna Mont, (from Cuba) 

 and 67. tomentosa Sur. (from Japan), are known to occur in similar localities. 



-) Top cells carrying branches are not, however, quite without instances. In small 

 fertile specimens yon sometimes find the top cell of the principal filament, when it is a 

 spore, carrying branches (pi. 2, tig. 13; pi. 4, fig. 16). 



