420 SUMMARY OF CURRENT RESEARCHES RELATING TO 



tion. It is attached to the substratum by an attaclnnent-organ which 

 varies considerably in its form and degree of development. The only 

 reproductive organ detected was a sporange, which may be stalked, and 

 is less often intercalary. The whole contents of this sporange, which 

 are coloured brown by phycophsein, clothe themselves with a cell- wall 

 within the sporange, and escape as a single large motionless spore, 

 formed non-sexually, the germination of which was followed out. The 

 spore contains four, or sometimes a larger number of nuclei ; and the 

 author sees in this a possible rudimentary formation of tetraspores, and 

 alliance with the Dictyotacefe, although in its mode of growth Haplo- 

 spora comes nearest to the Sphacelariacese and Ectocarpaceae. 



In habit and mode of growth Scaphospora speciosa closely resembles 

 Haplospora. It presents, however, two distinct kinds of reproductive 

 organs. The first, called by the author " oosporanges " and " oogones," 

 are usually intercalary cells, from which the whole contents escape as a 

 single " spore," which differs, however, from that of Haplospora in 

 having no cellulose-coat, and only one nucleus. Its germination was 

 not observed. The bodies of the second kind are multilocular sporanges, 

 from which escape a number of spores which are probably zoospores. 

 It is most probable that there is in Scaphospora a sexual mode of re- 

 production. Either the " spores " contained in the organs first described 

 are oospheres, and the others antherozoids, or, as the author thinks more 

 likely, the former are non-sexual spores, the latter zoogametes. 



Tilopteris Mertensii resembles the other two genera in its habit and 

 mode of growth, and Haplospora in the mode of production of its spores. 

 The author thinks it probable that the three genera may eventually be 

 combined into one. 



New Genus of Desmidiacese.* — Herr S. Stoekmayer proposes a new 

 genus of Desmidiaceae, Astrocosmium, most nearly related to Cosmarium 

 and Cosmaridium, which it altogether resembles in form, but differing 

 from them in having stellate chromatophores similar to those of 

 Cylindrocystis, in contrast to the axile chlorophyll-bands of Cosmarium^ 

 Penium, Closterium, and Mesotaenium, and the parietal chromatophores of 

 Spirotsenia. 



Crenacantha, Peripleg-matium, and Hansgirgia.f — From an ex- 

 amination of Kutzing's little known Crenacantha orientalis from Hebron 

 in Palestine, Prof. A. Hansgirg considers that it must be placed under 

 Chaetophoracese near to Draparnaldia. Eeinke's genus Entocladia must 

 now be sunk in Periplegmatium Ktz., of which there are two sections, 

 Entocladia vasirme, and Entoderma fresh-water; the author agrees with 

 Wildeman in placing Hansgirgia flagelUgera De Toni ( = Phyllactidium 

 tropicum Moeb.) under the genus Phycopeltis Mill. 



Trentepohlia.| — M, E. De Wildeman passes in review the described 

 forms of this genus, and enumerates twenty-eight which he considers to 

 be good species. He finds that T. aurea sometimes presents the cba- 

 acter of having its gametanges stalked, a character on which Gobi had 

 founded, in T. uncinafa, a distinct section of the genus ; but this species 

 must now be sunk in T. aurea. Characters based on the form of the 



* SB. K.K. Zool.-Bot. GeselL, xxxviii. (1888) p. 85. 

 t Flora, Ixxii. (]889) pp. 56-9 (1 fig.). Cf. ante, p. 259. 



X Bnll. Soc. K. Bot. Belg., xxvii. (1888) part i., pp. 79-83, part ii., pp. 22-4, 

 136-44, 178-82 (1 pi.). Cf. this Journal, 1888, p. 777. 



