320 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VI, IV

that the bird lived for about four weeks after the inoculation of the material
in the buccal cavity, possibly due to varying individual susceptibility, but in
that case the feathers had not been plucked and lesions were noticed only in the
mouth. The explanation appears to be that unbroken skin does not take the
virus from the body. Lesions of the oculo-nasal form of the disease were also
observed in subsequent passages of the same virus.

Doyle and Minett [loc. cit.] described the possibility of generalised symptoms
being set up by inoculation of the virus intravenously, subcutaneously and intra-
muscularly, although the lesions developed in a varying degree of severity.

In comparison with those cases where only localised cutaneous lesions deve-
loped, there was a greater tendency for fatal termination when generalisation
occurred, with the additional production of mouth lesions as was observed with
the strain under study. In view of its highly virulent nature it is being main-
tained at this Institute.

                                            SUMMARY

(1) A survey of the past work on fowl-pox and several other allied condi-
tions, now known to be etiologically one and the same, has been made.

(2) Experimental transmission of diphtheritic lesions from the mouth of
fowls has confirmed that the causal agent, a filtrable virus, is the same as that
which produces fowl-pox lesions on the skin in India.

(3) The Indian strain of fowl-pox virus is immunologically indistinguish-
able from the Weybridge strain.

(4) There seems to be a tendency for generalisation with this particular
strain of the virus (obtained from Cannanore, Madras) although this has not
been seen in the case of specimens received from other provinces in India, so far.

(5) Filtration experiments have been conducted with this strain of the virus
and Berkefeld ' V' filtrate has given positive results unlike Chamberland L. 3
and Berkefeld ' N ' filtrates.

                                  ACKNOWLEDGEMENTS

The authors wish to express their gratitude to Mr. F. Ware, F.R.C.V.S.,
I.V.S., Director of this Institute, for the facilities so kindly afforded by him, and
to Mr. J. R. Haddow, B.Sc., M.R.C.V.S. D.V.S.M., I.V.S., Scrologist, for
the valuable criticism and helpful advice kindly given by him, during the pro-
secution of this work. Our thanks are also due to Mr. J. S. Rao, Artist of this
Institute, for the illustrations.