Of iHi S( iiNCE OF Plant Bactf.riology 317 



was usable, " the best yet devised, and [would] probably come 

 into general use," among botanists. Another work which he 

 regarded " so very good that it deserves to find its way speedily 

 into every laboratory " was another German treatise, K. B. Leh- 

 mann"s and R. Neumann's Atlas und Grundrhs der Bakteriologie 

 jind Lehrbtich der speciellen bakteriologischen Diagnostik. On 

 March 20, 1897, he spoke about this before the Botanical Seminar 

 and in April reviewed it as current work in the Atnerican 

 Niiturn/ist.^''" This was "" a general work on bacteriology," he 

 said, " covering much the same ground as [C] Fliigge's D/c 

 Alikroorganisnien, but in a different manner. About 60 of the 

 more common animal pathogenic and saprophytic forms have 

 been studied more or less carefully and re-described according to 

 a pre-established scheme, so that their behavior on all the common 

 media may be readily compared." 



Smith was still studying the technique of titrating culture media. 

 "Authors," he wrote,"" 



have used phenolphthalein for titrating media regularly since 1894 and 

 recommend it for general use. . . . All the bacteria figured in the Atlas 

 were grown on media slightly alkaline to phenolphthalein, and most of 

 the 60 sorts bore the extra 10 cc. of alkali and the 10 and 20 cc. of acid. 

 This seems rather surprising to the writer and certainly cannot be assumed 

 to hold good for all species. My experience would lead me to select for a 

 universal medium a grade of alkalinity considerably less than the zero or 

 neutral point of phenolphthalein, i. e., one neaxer the zero of the best 

 neutral litmus paper, as I am satisfied that some species will not grow on 

 media as alkaline as here recommended. 



Since reviewing Theobald Smith's paper on the relation of sugars 

 to the growth of bacteria, he, presumably, had " given up . . . the 

 division of bacteria into acid and alkali producers." At least, the 

 distinction was not as hard and fast as it had been and he was 

 striving to improve his technical proficiency to study " the con- 

 ditions governing the production of acid " by each species. This, 

 in 1896. 



When the foregoing of 1897 was written. Smith had published 

 on two parasitic bacteria of plants. Bacillus tracheiphilus and 

 Bacillus solanacearum. He was completing his work on Pseud o- 



^"Udem 31(364): 312-314. 

 ^"Udem, 314. 



