J. Rennie and C. H. Sutherland 
201 
Larvae collected in Echt and Lower Deeside areas. 
Data for 1918. 
Lot 
Date 
Infected 
larvae 
Healthy 
larvae 
Total 
Percentage 
infected 
1. 
Feb. 20 
170 
434 
604 
28-1 
2. 
„ 27 
127 
243 
370 
34-3 
3. 
oo 
e, 
e. 
164 
524 
688 
23-8 
4. 
Mar. 1 
73 
386 
459 
160 
5. 
„ 6 
103 
442 
545 
190 
6. 
„ 7 
182 
819 
1001 
18-2 
7. 
„ 11 
56 
345 
401 
13-7 
8. 
„ 16 
42 
258 
300 
140 
9. 
„ 23 
79 
221 
300 
26-3 
Totals 
996 
3672 
4668 
21*3 
Larvae collected in Northumberland. 
For purposes of comparison we obtained a lot of larvae from the north of 
England. These yielded the following result: 
Infected Healthy Percentage 
Date larvae larvae Total infected 
Mar. 1 51 794 845 6*0 
In other areas where larvae were collected in fewer numbers, the parasite 
was also found and all our observations suggest that it is relatively abundant. 
During the season 1919, Tipula larvae were again collected and further 
data concerning the occurrence of Bucentes parasites were obtained. 
Search was made for Tipula larvae in fields on the College of Agriculture 
experimental farm at Craibstone, Aberdeenshire, from the month of December 
onwards. During December and January only very small numbers of Tipula 
larvae were found and of these none were infected with Bucentes . In February 
and March the numbers found increased slightly and out of 56 larvae, three 
were found infected, one of these harbouring four parasitic maggots. 
From April onwards appreciable numbers were obtained; the data for the 
season are shown in the table given below: 
Larvae collected in Lower Deeside and Lower Donside. 
Data for 1919. 
Lot 
Date 
Infected 
larvae 
Healthy 
larvae 
Total 
Percentage 
* infected 
Craibstone. 
1. 
April 7 
25 
349 
374 
• 
6-6 
2 . 
„ 11 
39 
237 
276 
141 
3. 
„ 22 
56 
429 
485 
11-5 
4. 
„ 25 
46 
288 
334 
134 
5. 
May 8 
l 
155 
156 
0-6 
No infected larvae obtained here during period May 9 to June 20. 
