778 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
strings of spores in the place of the usual cystocarps. They bear a close 
resemblance to seirospores, and appear to be developed in the absence of 
fecundation. 
Chreocolax.* * * § — Mr. H. M. Richards discusses the structure and 
systematic position of Chreocolax Polysiphoniee, parasitic on Polysiphonia 
fastigiata on the coast of New England. He succeeded in detecting 
not only the tetraspores, but also the trichogyne and accompanying 
organs, as well as the cystocarp. It is a true parasite, obtaining its 
nourishment from the tissue of the sea-weed on which it grows. The 
tetraspores develope from the terminal cells of the plant, and may be 
either tripartite or cruciate. The structure of the cystocarp appears to 
remove the genus from the Gelidiaceae, in which it ha,s hitherto been 
placed, and to transfer it to the Chaetangiaceae. The cystocarp resembles 
that of Chsetangium , and still more closely that of Galaxaura. The frond 
is immersed in a great mass of gelatinous matter. 
Sphacelariacese.l — Herr J. Reinke gives in further detail a mono- 
graph of this order of Phaeosporeae. Only one new species is described, 
Sphacelaria indica from Singapore, increasing the number of species of 
that genus from twelve to thirteen, while those of Cladostephus are 
reduced from three to two. 
Cladothele and Stictyosiphon. j: — Mr. G. Murray has made a fresh 
examination of Cladothele Decaisnei , from the Falkland Islands, hitherto 
placed, though doubtfully, among the Siphoneae. He found sporanges of 
the type familiar among the PhaeophyceaB ; and states that the alga is 
indistinguishable from Stictyosiphon , corresponding to that genus in the 
structure of the central axis and in the peripheral cells. The genus 
Cladothele must therefore be abolished, and its only species be united to 
Stictyosiphon , a genus of Punctariaceae. 
Cladophora.§ — M. E. de Wildeman confirms Gay’s observations on 
the production of rhizoids by Cladophora. When, under cultivation, a 
cell loses its cell- contents, it is common for an adjoining cell to put out 
rhizoids, which penetrate into the cavity of the dead cell, which they 
may traverse, and continue to grow in the surrounding fluid. Both 
C. glomerata and C. fracta undergo a great variety of modifications in 
cultivation, and it is probable that a large number of the very numerous 
species described are but modifications of one. The formation of bulbous 
or pear-shaped swellings is frequent, and the author has observed the 
production of rings in the cell-wall resembling those of (Edogonium . 
Hormidium, Schizogonium, and Hormiscia.|| — Prof. A. Hansgirg 
recapitulates the arguments in favour of his view that the aerophytic 
species of these genera are all connected genetically with one another, 
and with Prasiola, and replies to the observations of Gay, who is opposed 
to the theory of the polymorphism of the lower Algae. 
* Proc. Amer. Acad. Arts and Sci., xxvi. (1891) pp. 46-63 (1 pi.). 
t Biblioth. Bot. (Luerssen u. Haenlein) Heft 23, 1891 (40 pp. and 13 pis.). Of. 
this Journal, ante, p. 225. 
X Journ. of Bot., xxix. (1891) pp. 193-6 (1 pi.). 
§ Bull. Soc. Beige Micr., 1891, pp. 154-9 (4 figs.). Cf. this Journal, ante , 
p. 503. 
|| Bot. Centralbl., xlvii. (1891) pp 6-9. Cf. this Journal 1888, p. 1002. 
