76 Dr. E. Klein. [May 22, 



specimens and particularly by experiment. With matter taken from 

 the eruption vesicles and pustules of the udder, two calves were 

 inoculated into the skin of the groin ; here the same eruption made 

 its appearance : red papules, rapidly becoming vesicular, then pustular, 

 and then becoming covered with brown-black crusts, which two or 

 three days after became loose and left a dry healing sore behind. 

 More than that, the calves that showed this eruption after inoculation 

 became affected with severe broncho-pneumonia and with fatty 

 degeneration of the cortex of the kidney. In the two cows above 

 mentioned, on post-mortem, examination, both lungs were found highly 

 congested, cedematous, some lobules almost solid with broncho-pneu- 

 monia in the upper lobes and the upper portion of the middle or 

 lower lobe respectively; the pleura! lymphatics were filled with 

 serum and blood. Haemorrhages in the pericardium and lymph 

 glands, and necrotic patches were present in the liver. At the seat 

 of inoculation there was in both cases a firm tumour consisting in 

 necrotic diphtheritic change of the muscular and subcutaneous tissue. 

 In this diphtheritic tumour continuous masses of the diphtheria 

 bacillus were present; their gradual growth into and destruction of 

 the muscular fibres could be traced very clearly. 



It appears then from these observations that a definite disease can 

 be produced in the cow by the diphtheria bacillus, consisting of a 

 diphtheritic tumour at the seat of inoculation with copious multipli- 

 cation of the diphtheria bacillus, a severe pneumonia, and necrotic 

 change in the liver ; the contagious nature of the vesicular eruption 

 on the udder and excretion of the diphtheria bacillus in the milk 

 prove that in the cow the bacillus is absorbed as such into the 

 system. 



From the diphtheritic tumour by cultivation, pure cultures of the 

 diphtheria bacillus were obtained ; a small part removed from the 

 tumour with the point of a platinum wire, and rubbed over the 

 surface of nutrient gelatine or nutrient agar, yielded innumerable 

 colonies of the diphtheria bacillus without any contamination. In 

 cultural characters in plate, streak, and stab cultures, and in cover- 

 glass specimens of such cultures, this cow diphtheria bacillus coin- 

 cided completely with the human diphtheria bacillus, lout in sections 

 through the diphtheritic tumour of the cow a remarkable differ- 

 ence was noticed between it and the bacillus from the cultures ; 

 inasmuch as in the tissue of the tumour the masses of the microbe, 

 both iu the necrotic parts, as also where growing into and destroying 

 the muscular fibres, were made up of filaments and granular threads. 

 But that it was really the diphtheria bacillus was proved by culture 

 experiments and by cover-glass specimens. In the latter, the transi- 

 tional forms between typical diphtheria bacillus and long filaments 

 Avith terminal knob-like swellings, with spherical or oblong granules 



