ARTIFICIAL CULTUEE OF MARINE PLANKTON ORGANISMS. 427 



is not so important as the avoidance of rapid changes of 

 temperature. 



(9) A good north light, not exposed to direct sunlight, is 

 most suitable for the reariug-jars. 



(10) In determining the amount of water to be used in any 

 particular vessel, regard must be had to the amount of water 

 surface exposed to the air, which should be large in propor- 

 tion to the volume of the water. 



(11) A change of food is generally required, after the meta- 

 morphosis of the larvae. 



Bibliography. 



Cultures. 



1. Beijerinck, M. W. — " Das Assimilationsprodukt der Kohlensaure in 



der Chroniatophoren derDiatonieen," 'Rec. Trav. Bot. Neerland,' 

 i, 1904, p. 28. 



2. Benecke, W. — " tJber farblose Diatomeen der Kieler Fohrde," 



' Pringsli. Jahrb.; xxxv, 1900, p. 567. 



3. Breazeale. J. F. — "Effect of Certain Solids npon the Growth of 



Seedlings in Water Cultures," ' Botanical Gazette,' xli, 1906. p. 54. 



4. Drew, G. H. — "The Reproduction and Early Development of 



Laminaria digitata and L. saccharin a," 'Annals of Botany,' 

 xxiv, 1910, p. 177. 



5. Gill, C. Houghton. — See Van Heurck, H., 21 and 57. 



6. Karsten, G. — "Die FormJinderungen von Skeletonema costatum 



Gr'un und ihre Abhangigheit von iiusseren Faktoren," ' Wiss. 

 Meeresiinters. Kiel.,' N.F. iii, 1898, p. 5. 



7. " Ueber farblose Diatomeen," ' Flora,' Ixxxix, 1901, p. 404. 



8. Lockwood, S. M. — " Raising Diatoms in the Laboratory," ' Journ. 



New York Micr. Soc.,' 1886, p. 153. 



9. " Aberrant Forms in Cultivated Diatoms," ' Amer. Monthly 



Micr. Journ.,' 1893, p. 259. 



10. ■ — " Formes anomales chez les Diatomees cultivees artificielle- 



ment," ' Le Diatomiste,' ii, 1893-96, p. 9 ; ' Ann. de Micrographie,' 

 x, 1898, p. 1. 



11. Miquel, P. — " De la Culture artificielle des Diatomees," ' Le Diato- 



miste,' i, 1890-93, pp. 73, 93, 121, 149, 165 ; ' Le Micro. Pre- 

 parature,' v, 1897, p. 69. 



