20 BULLETIN 810, U..S. DEPARTMENT OF AGRICULTURE. 
TaBLe VI.—Resulits of inoculation with Bacillus pluton, ete—Continued 
Period 
Date of inoculations. of Results of inoculation. 
exposure. 
j Hours. 
Se] RUA IG Gah ae eh ci ae Tae Wee eee Se Soe SOE 21 | No disease produced. 
Sepl24,; 1915. 2 ee Be ae 2a ek Sure ae edie aoe eee meee | 23 Do. 
STOLE te) Ly tie ee Ca ele Sk naan RSM a Le 24 Do. 
UN ite ea) I ee eee i en ae Ane ae Les eer aa 26 Do. 
SG) Ls UGE oS SSS SoS SSS seks SS scsendas Seas oo Se ese: 26 Do. 
stijite 1S), USNS = = oe se sgo cases op see ee Sacdomads see sono scccc cece | 31 Do. 
Septs20 MOU. ca osc eee end a eee eee e eee eae eee | 38 Do. 
ANTIRES) ON ae AOR es aod ome Bars SEE aeee SoHo ane -SeococGesnasaee 40 Do. 
SG) Fed 9 (Ce a ee one Se eee me wee A SEE = dt Do. 
IGT OUD see onese Saee ee eee ie ee ee | 46 Do. 
Aug S23 A Qo. joc- bes soos tee Saeco e ce ERLE 5 ghee Bas aoe 63 Do. 
POX) ON Fey Sa 1) Us a ee ee ee es ae ae ee See es eee 95 Do. 
Observations recorded in Table VI show that Bacillus pluton in a 
dry film made from the contents of the stomachs of larve sick or 
recently dead of European foulbrood resists the direct rays of the sun 
for from 21 to 31 hours. 
RESISTANCE OF BACILLUS PLUTON IN WATER TO DIRECT 
SUNLIGHT 
In performing the experiments relative to the effect of direct sun- 
light on Bacillus pluton suspended in water, an aqueous suspension 
of the contents of stomachs of infected larve is exposed, in a Petri 
dish with the top removed, to the direct rays of the sun. After in- 
tervals reckoned in hours inoculations of healthy larve are made to 
determine whether the organism is viable. The direct method is 
used. Experiments made in this connection are summarized in 
Table VII: 
TABLE VII.—Resistance of Bacillus pluton suspended in water exposed to the 
direct rays of the sun 
Period | 
Date of inoculation. of | Results of inoculation. 
exposure. | 
1915. Hours. 
INA DA coe occ SRDS See SAE eee See oe See ase eee reeee 1 | European foulbrood produced. 
DOES Faas Sos oie SOR et SE a eae eee EOE ane 2 Do. 
ANGI 2 3s ioc veces ek ent See a eee eee ee SS 2 Do. 
ANUS isenoceedas seb Guddebod= Gusset oeon case doese coeesebeeess 3 Do. 
SAN PS Qe so os see ecck ee ee ea cio eae ena 3 Do. 
EAMES SUG Eo rae occ ee ae Sere eae mela Se ye ene ree eae 3 Do. 
RES DT Poa sat eww eran Re ee SE Ss Rs oi Re ee eee 3 Do. 
Sept. (a ssc.cac8 see aes oe nee ee See rennet 4 | Do. 
AUG -18 5 een acs tea eet ees cke hee ee 5 Do. 
UE WG oo on Sse cce Se Sec hacks Se eee eas eee eee 5 | No disease produced. 
Septsliicse soo 2e cee sGe seen ee sca ue oak eee ce ee en 5 Do. 
AEST ore estes Sos amelie ee a kee nn oer 6 | Do. 
Bs \(0 1074 | eA ae AR eet ee AO eae Bee Seis fe | Do. 
DOD U4 ene tee erie tee eer Shine ame ticines oa eee eee “| Do. 
1D YO saris ie remark aa tet el ets [eee eye ieee 5 A RS Se 8 | Do. 
Ya seeps ely ey eee nee oneness NE Ok eS CS 9 | Do. 
FUbhy 28s oaaehe cette ha BU Ee ie ks ee Be RS eee 10 | Do. 
NG C04 eas eae nee se iaane At Ge aa ae aha Ee ese 18 | Do. 
Table VII shows that Bacillus pluton, when suspended in water 
and exposed to the direct rays of the sun, was destroyed in from 
5 to 6 hours. 
