€36 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the cystocarps, indicating that neither were abortive. Thus the theory 

 is disproved that there is always an alternation of sexual and asexual 

 individuals in Polysiphonia. Further work is beino- undertaken with a 

 view to determining the sporophytic or gametophytic nature of this 

 generation by means of mitotic studies. 



Cell-contents of Fucoidege.* — H. Kylin has made a study of the 

 refractive bodies found among the cell-contents of the Fucoidese, a 

 subject which has been investigated by many botanists. He gives a 

 short summary of their views and then announces his own. In the 

 Fucoideffi there are three different kinds of bodies : fl) Those which 

 Schmitz called Phteophyceaj-sfcarch, and Kuckuck called pyrenoids ; 

 (2) those which Scbmitz called " mattglanzende, hyaline Tropfchen " 

 (dull gleaming hyaline droplets). These are most probably the " Fuco- 

 sankorner " of Hansteen, and are the " Physoden " of Crato ; {'X) fat- 

 drops. These tliree bodies are all discussed separately ])y the author. 



Antarctic Algge.f — L. Gain, reporting on the algte of the second 

 French Antarctic Expedition, writes a full account of the Algal Flora of 

 the Antarctic and Sub-Antarctic regions. The actual material collected 

 by the expedition, exclusive of diatoms, includes 41 marine species, of 

 which 7 species and one variety are new, and ;^)8 fresh-water species, of 

 which 1 species and two forms are new. The volume now published in- 

 cludes the special account of these collections, as well as a review of the 

 entire Antarctic flora. It is divided into four parts. The first deals 

 with the Antarctic region proper, namely, the zone lying below 60° 

 S. Lat. The results of former expeditions are successively passed in 

 review^ and followed by the systematic study of the French collections. 

 Then comes a general account of the biology of the alg^e in the region 

 of perpetual ice, and finally a comparison of the distribution of this 

 algal flora with tbat of other regions of the globe. 



In the second part the author reviews the marine flora of the sub- 

 Antarctic region, that is the circumpolar zone wbich is still under the 

 glacial influence. Then follow tables giving a complete list of all genera 

 and species in the Antarctic area, with a comparison of the Arctic and 

 Antarctic floras. It is seen that out of 409 Antarctic and 'iM'2 Arctic 

 species, only 71 genera and 57 species are common to the two regions. 

 Of these 57, one half is cosmopolitan and the other half occurs in the 

 temperate zone but not in the tropics. The third part is devoted to the 

 Antarctic fresh-water flora, and the fourth part is a review of our know- 

 ledge of the fresh-water flora of the sub-Antarctic regions. The book is 

 illustrated by text-figures and plates, two of which show photographs of 

 the districts explored. It is impossible in a short notice to give any 

 adequate idea of the importance of this work. 



Antarctic Marine Algae. — A. and E. S. GeppJ give a revised account 

 of the marine alga3 of the Scottish National Antarctic Expedition, col- 



* Arkiv f. Bot., xi. (1912) No. 5, 26 pp. (1 pi.). 



t Deux. Exp6d. Antarct. Tranijaise, 1908-10. La Flora Algologique, Paris. 

 Masson (1912) 218 pp. (8 pis., map, and figs.). 



X Scottish Nat. Antarct. Exped., iii. Botany (1912) pp. 73-83 (3 pis.). 



