ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 571 



animal is more or less lighted up, and may be photographed by the 

 aid of this bacterial luminosity. This phenomenon lasts 3 or 4 days 

 only, after which the animal returns to its normal condition. Warm- 

 blooded animals are not amenable to this phosphorescence. 



Bacterial Diseases of Plants.* — Dr. E. F. Smith contributes the 

 second portion of his reply to A. Fischer's " Answer." f The controversy 

 took its rise in statements made in Fischer's Lectures, 1897, wherein 

 it was laid down that, with the exception of the root-nodules of Legumi- 

 nosre, we know of no single instance where bacteria invade the closed 

 living cells of plants. According to Fischer, the bacteria are meta- 

 trophic and accidental, and there is no such thing as bacterial disease of 

 plants. Dr. Smith took exception to these and other assertions,^ and 

 his position may be summed up in bis own words, " there are probably 

 as many plant diseases due to bacteria as there are animal diseases 

 caused by these organisms " ; and good reasons were adduced in support 

 of the author's views which on a priori grounds alone were probable. 

 Fischer's " Answer " consisted chiefly of unscientific asseveration and 

 academic sarcasm. In his reply Dr. Smith discusses the question very 

 thoroughly, and with the advantage of personal knowledge and experience. 

 In the first part § he deals with the cases of B. amylovorus, B. olese, and 

 B. hyacinthis septicus, and in the second part with jB. iracheiphilus, 

 Pseudomonas campestris, and jB. Solanacearum. According to Fischer 

 the uninjured plant is impregnable to the attacks of bacteria, and even 

 if injured, the wounded area is soon shut off by the development of an 

 iupenetrable layer of corky tissue. The facts and arguments adduced 

 by Smith go to show that this hypothesis is at variance with observation 

 and experiments, and the position is supported by numerous photographs 

 and photomicrographs. 



Bacteroids of Leguminosae Nodules. |j— Dr. L. Hiltner claims that he 

 has known for some years that bacteroids can be produced in artificial 

 media ; and though he admits Stutzer's claim to priority of publication, 

 he desires to make clear his knowledge of the fact since the winter 

 1895-6. His observations also show that the shape of the bacteroids 

 does not depend exclusively on the species of host plant, but in some 

 measure on the species of bacterium. 



Acidophilous Bacteria.^ — In the course of investigations on the 

 so-called acidophilous bacteria met with in the stools of sucklings, Dr. 

 A. Kodella isolated an organism with the following characteristics. In 

 direct preparations from the stools it appeared as a rodlet 2-8 /x long, 

 straight or somewhat curved, and occasionally with rounded ends. It 

 was easily stained, and was not decolorised by Gram's method. In cul- 

 tures it exhibited an extreme pleomorphism, viz. short rodlets, filaments, 

 chains, and branched forms. It was a potential aerobe and anaerobe, 

 and grew best at incubation temperature. On agar the growth was slightly 

 raised, circular, and transparent. Bouillon was at first rendered turbid f 



* Centralbl. Bakt, 2" Abt., vii. (1901) pp. 88-100, 128-39, 190-9 (11 pis. and 

 43 figs.). Of. this Journal, 1900, p. 713. t Op. cit., v. (1898) p. 279. 



X Tom. cit„ pp. 271-8. § Tom. cit., pp. 810-7. 



|| Op. cit, vi. (1900) pp. 273-81. 

 «R Op. cit., 1* Abt., xxix. (1901) pp. 717-24 (1 pi.). 



