CTJLTimB OP SILKWOEMS, 
11 
healthy condition, by strict isolation and by submitting it to 
micrDscoi>ic or other ac^ltKrtion in thy maiHu^r heroafter explained. 
PEBEINE APPECITOG WILD MOTHS IN PEEAK. 
His Excellency the Governor some time back sent me, 
thronLrJi the Aetinjt,' British Ecsident, a nnml>er of the reports uf 
the Indian Silk Ccunmittee, and in one of llieae papers it waa iii- 
ineideiitiilly nientiom'd that pebrine, the disease wliich has bet>ii 
cansinfj such havoc in Perak, affects other genera of the Icpidop- 
teni besides the f^enuB to whi<th the silkworms lielong, and it 
occnrred to me that an examination of the \s'lld moths miti^ht 
l>e nseful. With this olijtx:t I Ik^^-uh a niicroBuojncal enqniry. 
and on the evening of the 1st February found a common wild 
moth badly affiected by pebrine. The bacteria wc^re identi<'al 
in form, size and refriugt;iice with those fi-om the silkwomis. 
with which they were careftdly compared, and there appears no 
reasoiialile cause to lead to the supposition that they are not 
the same micro-organism, though the actual proof— viz., inocula- 
tion — is wanting, and rather liard t^ apply, with any hojwe of 
obtaiiiinf,' positive results. 
This unlooked for and disagreealde discovery clearly indi- 
cates that tlie disease is endemic in Perak, and tliat, although it 
may Ite eradicated from all the silkwonns m the State, or a 
perieetly pure breed l>e iiif roduced, yet they will always l>e Bul)j*x*t 
to re-infection from coming into contact with wild pebrin<uis 
lepidoptera, or the virus emanating from these diseased insijcts. 
It was previonsly concluded that, owing to the isolated posi- 
tion occupied by Perak in regard to silk culture, infection was 
only U} lx> feared from outside, and that, given a licalthy brcrtid of 
worms and Y>roper precautions against the introduction of dis*?ast» 
from China or India, that the wonns woidd enjoy complete 
immniiity from peliriiic, Tliis hyjiothesiB is now apparently 
shown Ui l»e faUacions, and, inwtead uf once eradicating tlui 
disease, it will be nefesaary to jmrsue a <?ontinuous course of 
selection of seed, if the cultivation is ever to be carried on suc- 
cessfully. 
CONDITIONS NECESSABY TO ENSURE SUCCESS. 
Aa the reetilt of over two years' ol'Mservation and experiment 
on the growth of silkworms in Perak. I have arrive*] at the 
following roaclusions. 
The houses used U> rear tlii^ worms in should he small and 
detac'luHl from oim another. They should not be too lu^h, and Ijt' 
miwle fairly light:. They should Iw ustnl for only this one pur- 
jwse and sht>uld not l)e used as dwelliug-houses, nor stables, nor 
