40 



BEHAVIOR TOWARD STAINS. 



Beyond the fact that the flagelhini was stained with difficulty and 

 that old growths, whether in the plant or out of it, took stains feebl}^ 

 nothing- peculiar was observed, unless it be that the bacterial j^recipi- 

 tate resulting from growth was not stained in Dunliam's solution con- 

 taining methylene blue, and was stained in the same medium with 

 rosolic acid. The following are transcripts from records scattered 

 through my notes: 



Germs from an old culture in strongly alkaline (soda) beef broth 

 stained slowly and rather feebly in a saturated alcoholic solution of 

 gentian violet diluted with an equal bulk of distilled water and allowed 

 to act for half an hour. This culture had lieen killed by heat in the 

 thermostat. Germs from an old culture in acid beef broth which had 

 become alkaline, stained feebly in Ziehl's carbol fuchsin with ten 

 minutes' exposure. This, also, was undoubtedlj- a dead culture. 

 Germs from a month-old culture on sugar beet were exposed for some 

 time to a dilute watery solution of gentian violet, whereupon all the 

 zoogkea^ stained deeply, but tlie loose rods rather feebly. On long 

 exposure (over an hour) everything stained deeply. Germs from 

 sweet potato cultures a month old (zoogloese, rods, doublets, and 

 chains) stained feebly in a deep-colored Avatery solution of gentian 

 violet, although exposed for one-half hour. Germs taken from one of 

 the bright-yellow bundles of a diseased bulb (June 23, 1897) stained 

 feebly in water made deep red with Griibler's basic fuchsin. Germs 

 from the yellow bundles of another bulb (Feb. 3, 1808) showed a verj^ 

 weak stain after five minutes' exj)osure to water saturated with Grii- 

 bler's basic fuchsin. Exposed two minutes to water saturated with 

 gentian violet, the stain was much better, but not deep enough. The 

 rods from j'oung cultures stain readily. 



SYNOPSIS OF CHARACTERS. 



For convenient reference I have drawn up the following brief 

 account of this organism : 



Pseudomonas hyacinth i ( Wakker) . A yellow, rod-shaped organism, 

 multiplying by fission; ends rounded; single, in pairs, or 4's, more 

 rarelj" in the form of chains or filaments; motile b}^ means of one polar 

 flagellum. In the host plant, when the bundles are crowded full of 

 the 3'ellow slime and broken down, it is, generally, 0.8 to 1.2 hj 0.4 

 to 0.6 /<. In alkaline beef broth or on agar it usually measures 1.0 to 

 2.0 b3^0.4 to 0,6 //. In old cultures rich in sugar it often grows out 

 into long, slender chains, or into filaments (50 to 100 a^ long) in which 

 there are no distinct septa. Nonsporiferous. Color distinctly yellow, 

 but somewhat variable. Chrome yellow to pale cadmium in the host 

 plant, i, e., bright yellow^ (Ridgway's Nomenclature of Colors). On 



^ Saccardo's Jiavus and citrinus, but brighter (Chromotaxia) . The Standard Dic- 

 tionary's i/pjlojc III. lemon . and cauari/. approximately ( under Spectrum ) . Prang's 

 yellow. Plate I y. in the Prang Standard of Color. Popular Ed.. No. 1. 



