276 RECENT LITEBATURE ON ALGxE. 



their experiments in the germination of the oospheres, confirming 

 the results obtained by Prof. Falkenberg on the development of the 

 Aglnozo7iia-thdAliis. It is an interesting point that Prof. Falkenberg's 

 experiments of germination were made on fertilized oospheres, while 

 Mr. Church's plants were the result of parthenogenesis. In each 

 case a plant of the Aglaozonia-ty^e was developed, showing the so- 

 called " foot- embryo." From experiments in the germination of 

 the spores of Aylaozonia, Mr. Church shows that these may give rise 

 to a " protonematoid stage of Cutleria, which, on impoverishment 

 and exposure in a sunny window in summer, became precociously 

 antheridial" ; or the Aglaozonia-iovm may again be developed. 

 Attention is drawn to the fact that " polymorphy originates only in 

 the embryonic history, leading to the formation of the embryo, 

 designated the ' foot-embryo ' and the ' protonematoid embryo ' 

 respectively " ; and the author suggests that the cause of this 

 polymorphy may possibly be found in the influence of environment. 

 He then treats of the relation to temperature of Cutleria and 

 Aglaozonia and their consequent geographical distribution. Finally, 

 it is shown that if external conditions are not favourable for the 

 fertilization of the oospheres of Cutleria, the plant is reproduced by 

 parthenogenesis ; and the advance of Cutleria into northern waters 

 is accompanied by a diminution of the antheridia. The paper con- 

 cludes with speculations on the phylogeny of Cutleria, in which com- 

 parisons are drawn between it and Ectocarpus and the TilopteridecB. 



In Berichte d. deutsch. hot. Gesellschaft, Jahrg. 16, Heft 3, 

 Ap. 27, 1898, Dr. Kuckuck gives a short prehminary notice '' On 

 the copulation of swarmspores in Scytosiphon." He describes 

 shortly his experiments with H. lomentarius, and figures different 

 stages' of the process. This takes place, however, in comparatively 

 few cases, by far the greater number of spores coming to rest 

 without copulation. Dr. Kuckuck promises further details shortly 

 in Beitr. z, Kenntn, d. Meeresalgen. 



Mr. Herman G. Simmons pubHshes a second number of his 

 Algologiska Notiser in Botaniska Notiser, 1898, Hft. 3. This is 

 entitled " Einige Algenfunde bei Drobak," and forms an addition 

 of twenty algc^ to those already recorded from the Christiania- 

 fiord by Prof. Gran. Among them is a specimen of Phyllit is fascia 

 Kiitz., which resembles in certain points P. zoster ifolia, and appears 

 to unite the two species. Mr. Simmons, however, wisely refrains 

 fi'om making it a new species, and leaves the record under P. fascia. 

 A new JSlonostroma — M. tenue — is described and figured. It most 

 nearly resembles M. Lactuca, from which it is distinguished "by 

 its smallness, the form of the thallus, and the cell-structure." 

 The first distinction can hardly be considered a good one, especially 

 as no fruiting specimen has apparently been found, and the differ- 

 ences of the cell-structure might also be difficult to recognize. 



Flora^ Bd. 85, Heft ii. Ap. 23, 1898, contains a long and 

 important communication by Mr. Mitzkewitsch " On Cell-division 



