198 SUMMARY OF CURRENT RESEARCHES RELATING TO 



spores or cysts, both of which serve for the propagation of the organism. 

 Besides this, the cells of Gladophora are also capable of taking on a 

 palmella-condition under the influence of coal-gas. In certain cases, 

 during the formation of aplanospores, there is a marked diminution of 

 the number of nuclei in the interior of the cell as a consequence of 

 karyogamy. The structure of the nuclei of aplanospores, cysts, and such 

 like, differs from that of the nuclei in vegetative cells. The setting free 

 of the aplanospores, and apparently also of the cysts, as well as of the 

 palmella-like portions, takes place through a slimy degeneration of the 

 coats, and of certain parts of the contents of the mother-cells, whereby 

 it is made possible to eject the aplanospores from the cells. During all 

 these processes there takes place, in most cases, a tearing asunder of the 

 ri laments into separate pieces, whereupon the various parts continue their 

 growth in pseudorhizoidal fashion. Details are also given as to the be- 

 haviour of Mougeotia genuflexa in cultures. 



Naturalisation of Algae.* — 0. Sauvageau writes a note on the diffi- 

 culty of naturalisation of certain alga? in the Gulf of Gascony. For 

 instance, Ascophyllum nodosum and Himanthalia lorea, though they are 

 continually washed into the gulf in a fruiting condition, have never taken 

 foothold and become established. The same occurs with Gystoseira con- 

 mtenata and Sargassum vulgare var. fiavifolium. On the other hand, 

 Gystoseira granulata, which appeared to exist only north of the mouth of 

 the Gironde, has been found not far from Guethary, on rocks where it 

 has clearly become well established, and grows at the same level as 

 G. ericoides. Oddly enough, G. granulata is one of the species which is 

 seldom thrown up into the Gulf of Gascony. 



Marine Algae and Currents.! — C. Sauvageau deduces certain in- 

 teresting conclusions as to the direction of marine currents, from the fact 

 that floating species of Fucoideae are thrown up on the shores of the Gulf 

 of Gascony. Ascophyllum nodosum, Himanthalia lorea, and Gystoseira 

 granulata are often thrown up on the beach at Biarritz and Guethary, 

 and the author believes that they are carried northward from the coast of 

 Galicia by a surface current, which is too weak to influence navigation, 

 but is strong enough to float along marine algae. C. concatenata and 

 Sargassum vulgare var. flavifolium are also found among the shore debris, 

 and are presumably washed along the shores of Spain and Portugal from 

 the African coast. These slight marine currents can only be traced by 

 the help of marine algae, and have hitherto been overlooked. 



Hints on Collecting and Growing Algae. :f — J. A. Nieuwland gives 

 some important directions for the growing of algae brought home from 

 excursions. Large armaria are not necessary, the best results being often 

 obtained with gallon or two-gallon jars. The algae should, if possible, 

 be grown in the water in which they were found. The water should not 

 be changed, especially in the case of bog-algae, and when it is necessary 

 to renew the water not more than one-fifth the volume should be added, 



* C.R. Soc. Biol. Bordeaux, lxvii. (1909) pp. 830-32. 



t Tom. cit., pp. 829-30. 



\ Midland Naturalist, i. 4, Notre Dame, Indiana, 1909, pp. 85-97. 



