108 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
tlie only hybridisation obtained was the impregnation of oospheres of 
Fucus vesiculosus by antherozoids of F. serratus. 
Nuclear and Cell-Division in the Sphacelariacese. * — Mr. W. T. 
Swingle has followed out these processes in several species of Sphace- 
lariacese, especially in Stypocaulon scoparium. The following are the 
more important results. The apical cell is frequently of enormous size, 
even more than 1000 times that of the smallest tissue-cells. The size 
of the nucleus and of the nucleoles and the amount of kinoplasm are 
about in direct proportion to the size of the cell, but the chromatin 
framework is relatively much more strongly developed in the smaller 
nuclei. The cytoplasm is differentiated into two substances, the finely 
filamentous kinoplasm at the pole or poles of the nucleus and the foam- 
like trophoplasm. The kinoplasmatic radiations collect into a centro- 
some, which is always attached to the wall of the nucleus, and which 
multiplies by bipartition and remains during the whole period of rest. 
The old wall of the nucleus remains during the whole process of 
karyokinesis until the daughter-nuclei are formed, and then disappears 
suddenly. The formation of the achromatic spindle and of the cell- 
plate presents several peculiarities which are described in detail. 
Conjugation in Ectocarpus. f — Referring to the doubts cast by 
Oltmanns on the accuracy of the observations of Berthold and himself 
on theisogamous conjugation of the swarmspores (gametes) of Ectocarpus 
siliculosus and criniger , M. C. Sauvageau reaffirms their previous con- 
clusions, and maintains that Oltmanns’ explanation of the phenomena is 
founded on errors of observation. 
Endodictyon, a new Genus of Ectocarpacess.f — Herr H. H. Gran 
establishes this new genus of Phaeosporem, nearly allied to Ectocarpus. 
E. infestans is parasitic on the Bryozoon Alcyonidium Tiispidum, producing 
in it a dark olive-green colour, and forming on its surface irregularly 
spherical plurilocular sporanges. 
Grafting of Siphonese.§ — Dr. F. Noll has obtained, with one doubtful 
exception, only negative results in his attempts to graft or bud into one 
another species belonging to different genera of Siphoneae. A complete 
coalescence of growth was effected, but never any actual fusion of the 
protoplasmic bodies of the two individuals. Neither would portions of 
protoplasm from different genera coalesce, like those of the same genus. 
Coccoliths.|| — Dr. J. Jolv and Dr. H. H. Dixon find these organisms 
abundantly in dredgings from the Irish Channel. Not unfrequently they 
are contained within the body of an amoeboid organism, probably a species 
of Eifflugia, but the authors do not suggest any biological connection 
between the two. The coccolith consists of two very thin funnel-shaped 
elliptical valves ; a small valve attached by a central connection within 
a wider one, and provided with minute radial striations sculptured ap- 
parently on the outer or convex surfaces of both valves ; between forty 
* Jahrb. f. wiss. Bot. (Pfeffer u. Strasburger) xxx. (1897) pp. 297-350 (2 pis.) 
t Mem. Soc. Nat. Sci. Nat. Cherbourg, xxx. (1897) pp. 293-304. Cf. this 
Journal, 1897, p. 418. 
X Vidensk. Shrift. Ivristiania, 1897 (2 pis.). See Hedwigia, xxxv. (1897) Rep., 
p. 115. § SB. Niederrhein. Gesell. Natur. u. Heilk., Bunn, 1897, pp. 124-8. 
II Nature, lvi. (1897) pp. 468-9 (2 figs.). Cf. this Journal, 1897, p. 318. 
