74 
JAMES LAW. 
Fig. 8. Large pieces from a Radicular Odontome, weighing sixteen ounces, 
removed from the right superior maxillary region of an aged pacing horse, 
Chester B., 2:28^. 
Fig. 12. Radicular Odontomes of fourth superior molar with early longitudi¬ 
nal splitting, from a three year-old-colt. 
Fig. 13. a. Radicular Odontome of fourth superior molar with external fistulous 
opening, from an aged mare. 
b. Small Radicular Odontome of last inferior molar from a three year old horse. 
Fig. 9. The head of Chester B., three months after the removal of the 
odontome shown in Fig. 8, showing the odontome cavity and surrounding 
parts invaded by unhealthy granulations. From a photograph. 
Fig. 10. Right superior maxilla of Chester B., showing the large cavity 
previously occuiped by the odontome partially shown in Fig. 8. 
Fig. 14. Composite Odontome, from the region of the fang of the fourth superi¬ 
or molar from a one-year-old filly. 
a. Irregular mass of enamel, b. Dentine and cementum. c. Internal face 
of cyst studded with denticles, d. External surface of cyst, covered with 
smooth mucous membrane, e. Mass of cementum papillae from interior of 
cyst. 
Fig. 15. Longitudinal splitting of a tooth from lack of cementum between the 
inverted layers of enamel. 
Fig. 16. Oro-nasal fistula from destruction of a part of the palatine bone, the 
result of an odontome. 
KOCH’S METHOD WITH TUBERCULOSIS 
AND THE EARLIER USE OF CORRESPONDING PRODUCTS IN 
OTHER CONTAGIOUS DISEASES. 
By James Law, F.R.C.Y.S., Cornell University, Ithaca, N. Y. 
(A Paper read before the New York State Veterinary Medical Society). 
Koch has at last made known the source of his “ lymph.” 
It may be called a solution, in a mixture of equal parts of 
water and glycerine, of the products of the culture of bacillus 
tuberculosis, or of the growth of tubercle. Stated more dis¬ 
tinctly still, it is the poisonous chemical products of the 
growth of bacillus tuberculosis, or a part of such products. 
The fact that it is insoluble in alcohol suggests that it is more 
probably a ptomaine or organic alkaloid of fermentation, 
than a toxalbumin. To many, doubtless, the revelation will 
hardly be a surprise. The operation of the poison alike on 
the active local tubercle and on the tuberculous system, sug¬ 
gested as a factor the poisons normally acting in tuberculo- 
