508 



SCIENCE. 



[N. S. Vol. IX. No. 223. 



Finally, the fresh-water station should 

 be above all things an experimental one, 

 and in this direction the most valuable re- 

 sults are to be looked for, both from the 

 general scientific and from the technical 

 standpoint. To the scientist, this needs no 

 demonstration ; but it is essential that the 

 importance of such work, especially for fish 

 culture, be more widelj' understood. The 

 advance in agricultural methods in the 

 United States is unquestionably due in 

 large part to the development of a splendid 

 series of agricultural experiment stations in 

 which agricultural problems have been sub- 

 jected to intensive experimentation. Con- 

 trasted with this, conditions in fish culture 

 present almost the opposite extreme. Fish 

 eggs have been hatched in enormous num- 

 bers, but what is known of their subsequent 

 history or what has been done to insure the 

 safe development to maturity of the fish ? 

 Present methods have reached their limit 

 and the subject must be attacked from a 

 different standpoint. Fish culture should 

 receive by the liberality of state and nation 

 the same favors that have been extended to 

 agriculture, the use of permanent and well- 

 equipped experiment stations where trained 

 workers shall devote their time and energy 

 to the solution of its problems. Thorough- 

 ness and continuity are essential, for these 

 problems really deal with all conditions of 

 existence in the water. Of what does the 

 food of each fish consist, where is it found 

 and in what amount, how may it be in- 

 creased and improved ; to what extent and 

 how can the number of fish be multiplied, 

 and how far is this profitable ; what are the 

 best kinds of fish and what new varieties 

 can be produced ? These are a few of the 

 many questions to be solved. 



The problems outlined are indeed vast, 

 and yet we may be confident that their so- 

 lution lies easily within the power of the 

 human intellect, for they are all paralleled 

 in the history of the agricultural develop- 



ment of the race ; and man, relying upon 

 bis success in the past, may go forward 

 with supreme confidence to the attainment 

 of their solution in this new field. 



Heney B. Ward. 

 Zoological Laboratory, 

 The University of Nebraska. 



BRimiSSURE OF THE VINE AND OTSEB 

 PLANTS. 



Since the publication, in 1892, of the pa- 

 pers by Viala and Sauvageau describing 

 Brunissure of the Vine and the California 

 Vine disease as due to Plasmocliophora vitis 

 (Viala et Sauv. ) and P. californioa (Viala 

 et Sauv.) much interest has been mani- 

 fested in these supposed new parasites. F. 

 Debray and A. Brive in Kevue de Viticul- 

 ture, 1895, claimed to have found the para- 

 site in a large number of j)lants belonging 

 to numerous families and genera. They 

 made a new genus for the organism calling 

 it Pseudocommis vitis. By far the best work, 

 however, has been done by Viala and Sau- 

 vageau. A full discussion of their woi-k 

 with bibliography may be found in ' Les 

 Maladies de la Vigne, par Pierre Viala, Tro- 

 isieme edition 1893, pp. 400-413. Any 

 one who has observed for himself the pecu- 

 liar structures described would most likely 

 decide at once that they must belong, or be 

 at least closely related, to the genus Plas- 

 modiophora. The peculiar vacuolate plas- 

 modium-like structures may be best studied, 

 following the directions of Viala (in Mal- 

 adies de la Vigne), by slowly clearing the 

 sections or tissues in dilute eau de javelle. 

 The protoplasm of the host cell is said to be 

 dissolved, while that of the plasmodes re- 

 mains for a long time unattacked. The 

 plasmodes may then be colored with iodine 

 or other stains, bringing out their structure 

 very sharply. I have recently repeated 

 these experiments very carefully and find 

 everything described by Viala and Sau- 

 vageau in Vitis and also as described by 



