590 DISEASE IN WILD MAMMALS AND BIRDS 
sultation of the classification of the American Bac- 
teriologists would place it among Mycobacteriaceas. The 
facts that it is strongly aerobic, produces whitish efflo- 
rescence which may possibly be aerial hyphae and breaks 
up into short seg-ments, place it in the genus Nocardia. 
It seems, however, to belong to a division of Nocardia 
which is close to the Mycobacterium since the short ele- 
ments are swollen, cuneate and usually heavy, wliich is 
unusual in the more typical Nocardia. It is not, however, 
acid fast and therefore cannot be classified among the 
Mycobacteria. This culture seems to be a variety not 
heretofore described, and since its association with the 
disease is so definite, whether or not it be the cause, the 
name Nocardia MACROPODmARUM is proposed, because 
the kangaroos belong to the order Marsupialia, 
family Macropodidae. 
The discovery of these organisms within tissues is by 
no means easy even though the larger colonies may be 
located by staining. If Loeffler's method be used the 
central mass stains quite diffusely and the spreading 
mycelia around the edge stain faintly. For study pur- 
poses this stain is preferable to Gram-Weigert, since 
despite the positivity of the cultures, the blue dye can be 
removed very easily from sections and only with great 
care mil enough remain to permit tracing of the separate 
threads ; with Gram stain no detail can be made out in the 
centre of the colony, it being a diffuse blue. Careful 
search near the edge of these necroses will usually succeed 
in the discovery of a few mycelia stretching in between 
the mono- and polynuclears of the low grade inflammation. 
This is best seen in the margin of gastric ulcers, but may 
also be found in the cervical masses. AVhen searching in 
the pulmonary tissues the organisms are to be found in 
the bronchial exudate or at the edge of pneumonias. In 
one nasal mucosa the mycelia were dispersed, not growing 
in colonies as in localized inflammations. 
