l'2b 



comb, with short, close teeth; sometimes they are in 

 linear series, having very short joints, becoming thicker 

 until last segment, which is longer and club-shaped. 

 Some are swollen in the centre and drawn into threads 

 at extremities; others are ovoid like cocco-bacilli. 

 From Nocard's description the bacillus seems to take on 

 a variety of forms; it is found in pus and in free or 

 intercellular masses. It is an obligative aerobe; stains 

 always by Gram's method; grows in or on all media at 

 a temperature above 86° F. (best at 95° F. to 100.4). It 

 grows best on coagiilated blood serum where in 36 to 

 39 hours appear a number of colonies with a shining 

 surface, slightly raised in the centre, and appearing to 

 send a number of roots into the medium; these colonies 

 are white on serum from the horse, bright yellow on 

 serum from the ox, and gray on coag-ulated blood. 



Nocard, Lasage and Delmer believe that the princi- 

 I>al, if not the only, method of infection is by way of the 

 umbilical (navel) cord. Infection occurs during birth 

 or immediately following birth while the cord is soft. 

 Possibly it occurs in the vagina or vulva, or most likely 

 after the cord is torn or broken, and the young is on 

 the ground. Nocard attempted to infect calves by the 

 alimentary canal and by the respiratory passages, and 

 failed. But he succeeded by subcutaneous inoculation. 



The experiments of Nocard, Lasage and Delmer were 

 confined to calves in Ireland and on the continent of 

 Europe; and their tests may not be conclusive, yet the 

 evidence points very strongly toward navel infection. 



Law, Friedberger and Frohner, de Bruin, Moussu, 

 Deikerhoff, and others believe the disease is infectious. 

 Many attending or predisposing causes are given, some 

 of Avhich are aids to transmission or infection. The fol- 

 lowing are given by various authorities as causes, both 

 of infectious dysentery and of ordinary diarrhoea, 

 or dysentery : 



The voung or neAv-boru offspring failing to get the 



