194 



THE AMEKIOAN MONTHLY 



[October, 



of the kind. The vine was growing 

 vigorously, a healthy, beautiful speci- 

 men, raised from seed and at the 

 time about four feet high. 



In numerous instances, I have seen 

 within the cells of leaves and stems 

 of the red foliage plant, known to 

 florists as Achyranthes Gilsoni, simi- 

 lar movements ; but the decision is 

 not so confidently pronounced as to 

 the nature of the bodies. 



Notwithstanding such cases as 

 these, no special attention was given 

 beyond the passing wonder to the 

 matter ; nor was there much impor- 

 tance attributed to the observations 

 until circumstances occurred which 

 recalled attention to the records.* 



Having found that bacteria are 

 active agents in causing disease in 

 plants, especially such as we call 

 blight in the pear, apple, etc., and 

 having endeavored to find out how 

 the organisms gain access to the 

 inner, living tissues, these older ob- 

 servations were naturally remem- 

 bered and reinvestigated to ascertain 

 more positively the nature of the 

 active particles. Careful search in 

 the healthy tissues of the peer tree 

 proved fruitless, so of many others ; 

 but now and then the phenomenon 

 was observed, and conclusive proof 

 obtained regarding the bacterial 

 character of the moving atoms. They 

 did not simply oscillate and tumble 

 about, but progressively wiggled or 

 darted this way and that, in the field 

 of the microscope. A dilute solution 

 of iodine instantly stopped their mo- 

 tions. They were observed to repro- 

 duce themselves, or rather increase 

 in numbers and division. 



There were, in the best instances no 

 signs of unhealthfulness in the sup- 

 porting plants. In the case of hairs 

 consisting of a single row of cells the 

 basal one was found more often 

 tenanted, the others retaining their 

 vitality, though, of course, depending 

 on the basal one for their sustenance. 



* Proceedings Am. Asso. for the Adv. of 

 Sc. 1880, p. 583. Tenth Report Illinois 

 Industrial University, p. 18. 



During the summer of i88i, a 

 member of my family was twice 

 poisoned upon her arms by Rhus toxi- 

 codendron. The first time was early 

 in June, and this came from cau- 

 tiously handling a leafy twig of the 

 plant with gloved hands. Within the 

 following twenty-four hours, while 

 her hands showed no effects of the 

 poison, the forearms, which were 

 only partially covered at the time of 

 holding the twig in her fingers, were 

 manifestly poisoned. The skin be- 

 came red, swelling ensued, and after 

 the expiration of a day and a night 

 the inflammation rapidly increased 

 until by the forty-eighth hour there 

 was much feverish heat in the affected 

 parts, accompanied with pain, a burn- 

 ing sensation and intolerable itching. 

 Miliary vesicles now appeared, thickly 

 studding the skin, from which during 

 the two to four days much serum 

 was exuded — so much that cloths 

 laid upon the arm were soon wet 

 through. Upon drying, yellowish, 

 gummy matter was left, which some- 

 times formed during the night a 

 crust-like coating over parts of the 

 inflamed skin. Finally, from eight 

 to ten days after the exposure, the 

 swelling subsided, the exudation 

 ceased and desquamation took place, 

 during which and for a short time 

 thereafter the skin lost its usual sen- 

 sitiveness to the touch, as if the 

 nerves, too, had suffered. 



Upon microscopically examining 

 first the exuding serum, then the 

 contents of the eruptive vesicles, 

 multitudes of very minute spherical 

 or double-spheroid, motile bodies 

 were seen. From the vesicles espe- 

 cially, leucocytes were found, and 

 many of these contained within their 

 integument swarms of the moving 

 particles. All the characteristics of 

 these minute things gave conclusive 

 evidence that they belonged to the 

 group of organisms we call bacteria, 

 or the Schizophytes, and to that divi- 

 sion called by Cohn Micrococci. 



The second infection, more viru- 

 lent than the first, took place in 



