E. E. Atkin and A. Bacot 
535 
After 18 hours. 
The hatching is now general in all the tubes to which living yeasts or autolyzed 
yeast extract was added. 
Living yeasts (S. cerevisiae): 
The larvae in tubes Nos. 4, 6, 11 and 12 were distinctly in advance of those 
in tubes Nos. 2, 5, 9 and 10, to which autolyzed yeast extract was added. 
Tube No. 10, inoculated from No. 4, showed no advantage to larval growth 
as yet. 
Watery extract of brewers’ yeast: 
Tubes Nos. 1, 3, 7 and 8 do not show consistent results. In No. 1, 8 eggs had 
hatched—a fair proportion of the eggs present (about 22 to 25). In No. 3, 
only about 3 eggs have hatched out of some 20—25. In No. 7, 10 have 
hatched (about half the eggs). In No. 8, only 3 eggs have hatched out of 
15—20. 
After 36 hours. 
Watery extract of brewers’ yeast: 
Sterility had broken down in No. 7 and hatching was general. In No. 1 no 
more eggs had hatched. In No. 3 hatching was general, yet there is no 
evidence of infection. In No. 8 only 3 eggs had hatched. 
Living yeasts {8. cerevisiae): 
In these tubes the growth of the larvae is greatest in those which contain the 
fewest larvae. 
Autolyzed extract of brewers’ yeast: 
The larvae in tube No. 10 (infected) show no advantage as yet over those in 
Nos. 2, 5 and 9. 
After 4 days. 
Watery extract of brewers’ yeast: 
Tube No. 1, tests show that this tube is still sterile; many eggs remain dormant. 
„ No. 7 (infected), larval progress has been rapid. 
,, No. 8, sterility broke down shortly after the previous note; all the eggs 
have now hatched. 
M No. 3, hatching had been very general in this tube, but it still remains 
sterile. 
Autolyzed extract of brewers’ yeast: 
Tube No. 9, a bacterial growth was in progress and larval development was 
rapid. 
„ No. 2, had been infected; the larvae were progressing. 
„ No. 5, remained sterile; larvae showed scarcely any progress. 
,, No. 10 (infected), larvae showed varied progre.ss; a few were well grown 
in third instar, others were still small in first or second instar. 
After 18 days. 
Watery extract of brewers’ yeast: 
Tube No. 1 (sterile), none of the larvae had passed their first moult. 
„ No. 3 (sterile), none of the larvae had passed their first moult; all dead 
but three. 
,, No. 8 (infected), varied growth in second, third and fourth instar. 
