The new era., 1909-10-28
cRo<dF Gex1NYS jvxezsf oN1xx Na0al

regarded by DR.. A. E. Shipley. F. R.
S.. who is the chief authority in the
present band of investigators, as the
real offender. and he has made valu-
able contributions to the knowledge
of its life history. Although great
caution is displayed by DR.. Shipley in
giving any statement as final, 1t seems
fairly well established that. owing TO
some earlier cause which reduces the
birds vitality and powers of resist
ance, these parasites are able to de-
velop to such an abnormal extent
that the bird succunibs to their at
tacks. In some Instances the grouse
appear to recover. but as Mr.. E. A.
Wilson. the field naturalist to the
committee, points out, some of the
early symptoms Of grouse disease
might be confounded with those of
moulting
This brings US to the predisposing
causes which make a grouse unable
to resist the chronic wasting form of
illness. Is 1t possible that Prof. Klein
was right and that a form of pneu.
monia exists among the birds. which.
even II 1t does not carry them on. pre-
disposes them to injury from the
wasting form of the disease? It can
not be said that In the interim reports
of the committee of inquiry any great
leaning to this view Is to be discov.
cred. During 1905. 1906 and 1907 the
very large number of field observers.
amounting to several hundreds, asso
ciated with the committee did not de-
tect one instance of the acute pneu.
monic form Of the disease. and Mr..
Wilson has observed that some Of the
symptoms relied on by Prof. Klein in
his published monograph are not con.
elusive evidence of its existence. II
seems. therefore. that the committee
are rather reluctant on the one hand
to admit Klein's grouse-pneumonia.
anu yet are at loss to explain why
otherwise 1t Is that the birds become
susceptible to the wasting sickness.
Within the last few days the Zoo
logical society Of London has issued
series of papers by DIR. A. E. Ship
ley on the parasitic organisms OF
which the grouse is host. In these
papers the value to be attached to Dr.
Cobbold's early observations is fully
apparent. The larvae OF the thread.
worms which prey upon the red
grouse exist in abundance in every
square foot Of heather. and no doubt
is felt that under certain conditions
| at present undetermined-the lar.
| vac reach the two important organs
of the bird. the lungs and the liver
Referring to the extreme difficulty, in
consequence Of their microscopic di
mensions, OF finding the ova upon the
heather. either on the stalks or in the
buds Thought they exist in countless
thousands). DR.. Shipley mentions 8
new and peculiarly successful method
OF examination. which he hit upon IN
the autumn of last year. whilst visit
| ing at Beaufort castle. A handful oi
heather placed in a bottle is soaked
in little water for some hours; ulti
mately the sediment after suitable
treatment is examined microscopical
ly. for larvae. and that with unvaryins
wealth Of material. 1t is stated tina,
the exact relations Of the grouse-ily
tOrnithomyia lagopodis) to the grouss
Is not known. 1t Is. however. believed
to suck Its blood, and 1t will certainly
bite human beings. The fly is provid
ed with a pair Of great hooks on i..
feet. and altogether this insect has .
decidedly sinister aspect. 1t occur.
freely In larders where freshly killed
grouse have been placed.