Algae. 13 



the four years, it becoraes stationary also along the Belgian-Dutch 

 coast and extends along the west coast of Norway, but does not 

 reach the English eastcoast nor the English Channel; with under- 

 currents it penetrates to the Baltic through the Danish Waters, but 

 does not stay there, the water being too fresh. 



It is an eurythermic and euryhaline organism, being found in 

 water of 1°0— 15°6 C° and 7,5— 35,3% salinity, but thriving well 

 only in water of 2°2— 12°6 C° and 27,0 (30,0)— 35,0% sal. 



The last chapter treats of the applicability of the facts found to 

 elucidate hydrographical questions; but here is not the place to re- 

 view that part of the paper. It will be sufficient to quote the final 

 sentences: „The aim of the paper has been to follow the immigra- 

 tion of Bidd. sin. and to show its importanee for hydrography as a 

 means of determining the direction and rate of flow of the oceanic 

 currents; an endeav^our has also been made to picture the outer 

 conditions under whieh the immigration of this species has success- 

 fully proceeded before our eyes; in 1903 — 1907 the North Sea has 

 become richer by a planktondiatom which is of importanee for the 

 general characterisation of its plankton." 



A large series of tables contains the material of observations 

 upon which the paper has been based. C. H. Ostenfeld. 



Ostenfeld, C. H., Smaa Bidrag til den danske Flora. V. 

 [Small Notes on the Danish Flora. V]. (Botan. Tids. XXIX. 

 3. p. 326—330. Köbenhavn, 1909.) 



New records on plants of the Danish Flora. As an interesting 

 addition to the flora it may be mentioned that Thesium alpinum 

 was discovered, but only one speeimen, in Jutland; it is a consi- 

 derable amendement to its geographical ränge. Another point of 

 interest is that Convolvulus soldanella, hitherto not known as far 

 north as the Jutland peninsula, has been found in two places 

 along the shores (on the sea-dunes) of the northermost part of the 

 peninsula, N. of the Limfjord. 



A variety of Sonchus olevaceus, named by Neuman in 1889 

 var. albescens, but little known, has been reformed and has proved 

 to breed true under eultivation. 



The larger number of the records belongs to species aeeiden- 

 tally introduced by man. C. H. Ostenfeld. 



Ostenfeld, C. H. et C. Wesenberg-Lund. Catalogue des espe- 

 ces de plantes et d'animaux observees dans le plankton 

 recueilli pendant les expeditions periodiques depuis le 

 mois d'aoüt 1905 jusqu'au mois de mai 1908. (Publications 

 de Circonstance, 48, Conseil permanent international pour l'explo- 

 ration de la mer. IX, 151 pp. Copenhague, A. F. Host & fils, 

 juillet 1909.) 



The plankton lists from the collections made during the quar- 

 terly cruises of the investigation steamers of the International Co- 

 operation for the study of the Sea are published in the periodical 

 „Bulletin" issued by the Central Bureau of the Cooperation. As these 

 lists are tabulated and owing to their extension difficult to survey 

 and use, the authors have made a synoptical Catalogue of them, 

 as far as the years 1905 to 1908 are concerned; a similar catalogue 

 for the plankton lists of 1902 to 1905 has previously (in 1906) been 

 published. 



