ZOOLOGY AND BOTANY, MICKOSOOPY, ETC. 555 



50° to 70° with the vertical. Neither in the growing nor in the mature 

 portion of the rhizoid could the author detect the least evidence of any 

 variation in the thickness of the cell-wall, or in the distribution of the 

 protoplasm on the two sides of the growing organ. 



Algae. 



Connection of the geographical distribution of Algae with the 

 chemical nature of the substratum.* — Sig. A. Piccone points out the 

 argument in fiivour of the view that Algre do not absorb nutriment 

 through their organs of attachment derived from the fact that the same 

 species will be found growing apparently indifferently under totally 

 different circumstances. He gives a list of 17 sjjecies ordinarily rupi- 

 colous which are found not unfrequently attached to the shells of 

 molluscs or growing epiphytically upon other sea-weeds, and of two 

 species ordinarily fucicolous which he found attached to a variety of 

 other sea-weeds belonging to the Floridea3 and the Chlorosporeae. 



Algae of the 'Gazelle' Expedition.f — The Alg£e collected in this 

 expedition have been worked out by Herr E. Askenasy, with the assist- 

 ance of M. Bornet and Herren Grunow, Hariot, Moebius, and Nordstedt. 

 The following new species are described : — Cyanophycese : — Microchsete 

 vitiensis. Conjugatse : — Gymnozyga longicollis. Confervaceas : — Ana- 

 dyomene reticulata. Characefe : — Nitella duaJis. Siphonocladacefe : — 

 Halimeda macrophysa, Caulerpa delicatula. Pha3ophycefe : — Ectocarpus 

 Constancise. Fucacete : — Cystophyllum notlium, Sargassum pulchellum, 

 S. Maiiritianum. Floridefe : — Hildehrandtia Lecannellieri, Chantransia 

 Naumannii, Bhahdonia decumhens. 



Dictyosphseria farulosa consists of large cells, 0'5-2 mm. in diameter, 

 between which are several rows of smaller cells ; the structure of the 

 walls of the latter is very peculiar. Young plants have the form of a 

 closed sac, resulting from the segmentation of large cells, containing 

 numerous nuclei, starch-grains, and peculiar brown elliptical bodies. 

 The structure of Halimeda is described in detail. Among the Meso- 

 gloeacefe the author regards the genus Myriocladia as hardly sufficiently 

 distinct from Mesogloea. In Galaxaura (ChEetangiacefe) the structure 

 recalls that of Halimeda. Straight branching medullary hyphae send 

 out branches at right angles which end in the cortical fibres. The only 

 fructification observed consisted of cystocarps. In Corynospora Wiiller- 

 stjrfiana (Ceramiacete) polyspores were observed closely resembling those 

 of Pleonosporium. Marchesettia spongioides (Areschougiaceae) the author 

 regards as undoubtedly furnishing an example of symbiosis between a 

 Floridea and a sponge. The species of sponge probably varies. The 

 only reproductive organs observed were tetraspores. 



Development of Tissues in Florideae-I — Prof. N. Wille gives more 

 detailed illustrations of the six groups into which he divides the Florideje, 

 dependent on the mode of growth of the frond and the development of 

 the different tissues. 



* Notarisia, iv. (1SS9) pp. 667-71. 



t Algen (Forschungsreise S.M.S. Gazt-lle), Th. 4, Botuuik, Berlin, 1SS8, 58 pp 

 and 12 pis. See Hot. Centralbl., xxxvii. (18S9) p. 112. 



t Nova Acta K. Leop.-Carol. Akad., lii. (1888) pp. 49-100 (G pis.). C. this 

 Journal, 1886, p. 658. 



