Physiologie. Algae. 41 l 



ducing them received the word tinctoria ior their specific name, such as 

 Genistet tinctoria, Antltemis tinctoria, Serratula tinctoria. The best 

 yellow is produced from Reseda luteola (Weld), its tinetorial properties 

 being due to the alkaloid luteolin. Genista tinctoria gives a good per- 

 manent yellow; formerly it was used as a green dye. Three of the 

 Composita, Anthemis tinctoria, Chrysanthemum Segetum, Bidens tripar- 

 tita, give yellows approaching orange on addition of alum. Yellows 

 have also been obtained from the fresh inner bark of Pyrus Malus, and 

 Fraxinus excelsior, and from the root of Rumex obtusifolius. 



Several browns are obtained from the bark of the AI der (Alnus 

 glutinosa) : treated variously with potash, tints of red are obtained; and 

 shades of black in the presence of ferrous sulphate. These colours are 

 all tannin derivatives. Similar colours are obtained from the bark of the 

 Birch (Betula alba) and the Oak (Quercus Robur). Yellow browns are 

 obtained from the Ling (Calluna vulgaris), and the bark of Rhamnus 

 Frangula and R. cathartica). A fine russet brown is obtained from the 

 Liehen Sticta pulmonacea ; and „crottle" browns from species of Par- 

 melia. The best brown is obtained from fresh walnut husks (Jnglans 

 regia). Not far behind it is the colour obtained from the rhizome of the 

 white Water-Lily (Nymphaea alba). 



The best green is obtained from a ground dye of Woad (Isatis tinc- 

 toria) followed by Weld (Reseda luteola): less brilliant greens, from the 

 ripe berries of the Privet (Ligustrnm vulgare) with alum, and from the 

 flowering shoots of the Reed (Phragmites communis) with ferrous 

 sulphate. 



The dull reds of Potentilla Tonnentilla and Comarum palustre 

 require a trace of potash to develope them. The root of Galium verum 

 yields a madder red: a colour approaching red is obtained from the 

 fresh inner bark of Betula alba. 



Only one plant yields a blue colour : Isatis tinctoria, the Woad. 



Spebimens of dyed wools were exhibited at the meeting of the Royal 

 Horücultural Society. Vines (Oxford). 



Ostenfeld, C. H., i n Forch, Carl, Kundsen, Martin und Sörensen 

 S. P. L. : Berichte über die Konstantenbestimmungen 

 zur Aufstellung der hydrographischen Tabellen. 

 (Kgl. Danske Vidensk. Selsk. Skv., 6 Rokke, naturvidensk. 

 und mathem. Afd. XII, 1. Köbenhavn 1902.) 



The main part of this treatise is of purely hydrographical 

 interest, but on p. 18 — 22. 



C. H. Ostenfeld has published lists of the organisms in 

 severai plankton-samples, collected together with the water- 

 samples in the year 1900. 



The general results of the examinations are: 



1. Baltic Sea, May. The plankton is poor, consisting 

 of Diatoms and Copepods. 



2. Kattegat, April-May. The plankton is very rieh as 

 well with respect to the quality as to the quantity; Diatoms 

 predominant. 



3. Bay of Biscay, June. The plankton consists of a few 

 Peridiniaceae and Copepods only. 



4. Str. of Gibraltar, October. Many species of Peridi- 

 niaceae, but few individuals of every species. 



5. Mediterranean Sea, June. Many species of Peridi- 

 niaceae, especially of the Genus Ceratium. 



