/OOLOGY AND BOTANY, MICROSCOPY, ETC. 677 



.ffigagropila.* — Lorenz v Liburnau has investigated the conditions 

 under which the organism known as JEtjagropila Sauteri is formed in 

 the Zeller See and elsewhere. The hollow balls are unquestionably 

 simply a mode of growth, dependent on external conditions, of a species 

 of Cladophora. The special condition favourable to the formation of the 

 balls appears to be a nearly uniform illumination on all sides, which can 

 occur only in shallow water, where they are constantly rolled about by 

 the waves. The formation of these balls is the only character by 

 which JEgagropila Sauteri can be distinguished from the polymorphic 

 Cladophora glomerata or from C. muscoides. 



Transplantation and Structure of Protoplasm in Bryopsis. t — 

 S. Prowasek has made further study of the phenomena connected with 

 the transplantation of a portion of the structure in Bryopsis plumosa. 

 He states that — excluding the phenomena of conjugation — a complete 

 fusion of two masses of protoplasm does not take place. The movement 

 of the protoplasm in Bryopsis is, correctly speaking, a movement 

 neither of rotation nor of circulation, but a simple streaming. It 

 usually begins at the apical end of the pinna or portion of a stem, and 

 runs down all sides to the base ; only rarely were counter-streamings 

 observed. Light plays a large part in the life of Bryopsis ; in the dark 

 it loses its characteristic form and assumes a filiform woolly character. 

 The elongated chlorophyll-bodies have an obscurely mesh-like structure ; 

 they often contain two or three pyrenoids, but usually divide inde- 

 pendently of their position. 



Acicularia and Acetabulum. % — M. A. Howe gives a very full 

 description of the rare and beautiful species Acicularia Schenlcii. 

 Described at first as a species of Acetabularia, the author now identifies 

 it generically with the fossil Acicularia Pavantina. 



Thermal Alga.§ — An alga already known as Protococcus vulcanicus 

 and Pleurococcus sulphurarius is described by G. A. Galdieri from the 

 hot sulphur-springs of Pozzuoli. It consists of a single spherical cell 

 3—12 /jl in diameter, of a blue-green colour. The chromatophore 

 completely clothes the inner surface of the cell-wall. The cell-sap con- 

 tains a number of colourless, strongly refringent pyrenoids [? Ed.], 

 which are in constant active motion. No nucleus or cilia could be 

 detected. 



Fungi. 



Sexuality of Fungi. || — F. Oltmanns sums up the results of all 

 recent observations of importance on this subject, and concludes that 

 the evidence is in favour of De Bary's view of a true sexuality rather than 

 of the opposing view of Bref Id. This is especially the case with the 

 Ascomycetes, and points to a closer affinity of this class of Fungi with 

 the Florideae than has generally been admitted. It is not, however, 

 necessary to assume that all organs which were originally of a sexual 

 character have retained that function, as with the " spermatia " of 

 lichens. 



* Verhandl. k. k. Zool.-bot. Gesell. Wien, li. (1901) pp. 363-8. Cf. this Journal, 

 1900, p. 92. t Biol. Centralbl., xxi. (1901) pp. 283-91 (13 tigs.). 



X Bull. Torrey Bot. Glub, xxviii. (1901) pp. 3^l-oi (2 pis.). 



§ Kend. Accad. Sci. fis. e mat. Napoli, v. pp. 100-4. See Bot. Centralbl., lxxxvii. 

 (1901) p. 84. || Biol. Centralbl., xxi. (1901) pp. 433-42 (5 figs.). 



Dec. 18th 1901 2 z 



