58 



Veit Brecher Wittrock. 



Obs. Having obtained material for examination of this species 

 (by the mediation, as has been mentioned before, of D:r J. Rostafinski), 

 when a great part of the essay was already printed, and having thus 

 been unable to give due attention to the morphological peculiarities of 

 this species in the general account of the morphology of the order, 

 I may be permitted, to give in this place an exposition of its most essen- 

 tial morphological peculiarities. They are l:o that P. oedogonia (Mont.) 

 nob. is the only one among P. isosporece that has the system of ramifica- 

 tion of the cauloid so strongly developed as to possess regularly branches 

 of three degrees; 2:o that the rhizo'id part of the thallus sometimes 

 attains so strong a development that it forms branches of two degrees; 

 3:o that the subsporal cells are often so rich in protoplasmatic contents, 

 that they have the power of developing one, and now and then even 

 two, branches; 4:o that the mother-cells of the spores have often the 

 power of forming not only one spore, but successively even two ; f ) 

 5:o that the spores formed in the normal manner, remaining attached 

 to the mother specimen, sometimes germinate in the same manner as 

 the prolific cells, i. e. by developing a branch from one of their sides 

 (or sometimes a branch from each of its two sides). 



5. Pithophora Cleveana nob. 



Diagnosis. Principal filament of the cauloid part of the thallus 

 in fertile specimens on an average 75 ft thick, with branches commonly 

 of only one degree, but now and then of two; branches as a rule soli- 

 tary (rarely opposite in pairs); helicoid cells pretty common; spores 

 single (rarely in pairs), partly inclosed, partly terminal; the inclosed 

 spores cask-shaped or more rarely subcylindrical; thickness of the cask- 

 shaped spores on an av. 102 ^ 7 longitude 216 ( u; the terminal spores 

 cask-shaped with the upper end conical and the top somewhat rounded, 

 on an av. 93 n thick and 232 ^ long. — Plate 2, figs. 13 — 15; pi. 4, 

 figs. 12—18; pi. 5, figs. 1—8. 



[P. terrestris subgracilis et subbrevis, filo principali partis thalli cauloidese 

 speciminum fertilium circa 75 crasso, ranios plerumque unius solum ordinis, in- 

 terdum autem duorum, singulos vel raro binos oppositos emittente ; ramis cellulis beli- 

 coideis saepe praeditis; sporis vel inclusis vel terminalibus, solitariis (raro geminatis); 

 sporis inclusis subelongato-orculpeformibus vel rarius subcylindricis, iliis c:a 102 f.i 



') In the peculiarities indicated in the points 3 and 4, P. oedogonia (Mont.) nob. 

 sliows a not inconsiderable conformity with P. Zclhri (v. Mart.) nob. among P. hrte- 

 rosporece. 



