DIPHTHERITlC FORM OF FOWL-POX IN INDIA                            319

                                                                 TABLE III

                                                         Filtration Experiments

          * The material in all the five cases was derived from a single strain (Buccal lesions of Fowl No. 228 which
            reacted to specimen No. 397/1935).

                                             DISCUSSION

From the results of the transmission experiments it is evident that the diph-
theritic form of fowl-pox is also observed in India, besides the cutaneous form,
and that the two forms are due to the same virus, which is immunologically
indistinguishable from our stock Weybridge strain of this virus.

Positive results with the Berkefeld ' V' filtrate of the material originally
obtained from the buccal cavity of fowl No. 228, exhibiting the diphtheritic
form of fowl-pox and inability of the micro-organisms normally inhabiting the
buccal cavity of fowls to produce such lesions without the help of the virus, in
spite of scarification, show that the above described lesions are due to a specific
virus.

With this particular strain of virus, buccal lesions developed almost invari-
ably, in addition to the cutaneous lesions, even when the material was inoculated
only on the feather follicles. But when the buccal cavity was inoculated with
the material it killed the bird rather quickly and no distant cutaneous lesions
were able to develop through generalisation, in spite of pulling out the feathers
and thereby injuring the feather follicles. It was only in one case (fowl No. 256)