390 TIMOTHY RICHARDS LEWIS. 



gent molecule figured at ha as seen by Powell and Lealand^s one- 

 sixteenth immersion — but frequently the extremely translucent 

 filament attached to it extends beyond the ' spore ' at either 

 end (fig. ^l), thus showing that the filament is not formed of 

 plasma which had proceeded out of the ' spore,' but is, in reality, 

 a tube enveloping it. It has been observed already that the 

 observers who maintain that these refractive bodies germinate, 

 base their opinions on diff^erent grounds.^ Their figures in 

 most cases agree, but their interpretations differ. 



It may be suggested that, although the bacilli found in the 

 decomposing blood of healthy animals do produce spores, they 

 are not of the same character as the spores found in Bacillus 

 anthracis. To this it may be replied that Cohn states that the 

 spores in the latter are identical in appearance and run through 

 the same developmental stages as the spores of the Bacillus 

 suhtilis of hay-solutions, so that the remarks which I have ven- 

 tured to make regarding the ' spores ' of the bacillus of ordi- 

 nary blood apply equally to bacillus of hay-infusions, for I have 

 been unsuccessful in witnessing anything like the germination 

 process in the ' spores ' of the latter also. Nor were the 

 ' spores ' which formed in bacilli associated with the anthracoid 

 blood of the horse observed to germinate. 



With regard to specific distinctions which have been based on 

 the differences of size which microphytes of this character pre- 

 sent — specific distinctions which, in all probability, will be still 

 further advocated in the future — it is of interest to note that 

 the bacilli found in the blood and tissues of animals which, at 

 the period immediately preceding their death, had been per- 

 fectly healthy, manifest considerable latitude in this respect. 

 The following extracts from my note book may serve as illustra- 

 tions of this, and, at the same time, furnish a brief epitome of 

 the changes which bacilli-filaments undergo under very slightly 

 varying circumstances. The first series of extracts will refer 

 to bacilli of a smaller size than ordinarily seen. The notes run 

 as follows : — " Killed two mice yesterday and examined one of 

 them to-day, twenty-four hours after death. The red blood 

 cells from blood taken from the heart fairly well preserved. 



1 Since this paper was printed I liave seen a very interesting paper by 

 Brefeld dealing willi this subject (' Untersucliungen der SpaUpilze,zuniachst 

 der Gattung Bacillus '}, in whicli it is maintained that neither Cohn nor 

 Kocli could have seen llie actual germination of these bodies, as, according 

 to his (Brcfeld's) own observations, the process takes place in a different way 

 from that described by them. This distinguished botanist states that he 

 has satisfied himself that germination takes place at« i-ight angle to the long 

 axis of the "■spore," and that the act takes place more rapidly after prolonged 

 boiling. It will be recollected that Dr. Ewart found tiiat the 'spores' 

 were killed after being boiled for only two minutes. 



