244
H . KLOMP
I F
JULY 16-3l
AUSUST 16-31
10- - - -
0
YI 20
20
30
3 5
LO
15
S E P T . l - 1 5
-
-
d
5
a
b
c
SUMMARY
10
15
10
25
30
16
4 1
15
SO
WlmW OF HEAD CAPSULE (MICROMETER UNITS)
FIQ. 11. Results of measurements of the width of the head capsule of larvae collected in
the field in 1957 (Both sexes included). The majority of first instar larvae (histogram 1)
originated from eggs collected in the field and reared in the laboratory. The measurements after 15 October are those o f nymphs collected in the funnels described on p. 220.
The bottom graph is a summgry of the others. The numerals 1, 2, and 3 indicate the
histograms of the first, second and third larval instar; 5 denotes the final instar; 4a-c
are explained in the text. One micrometer unit = 0.045 mm.
effect (Weber, 1954; Wigglesworth, 1953). The fraction of individuals
passing through six instars varies from year to year (see p. 258).
The other environmental effects on size will be discussed in the next
section.
H . KLOMP
I F
JULY 16-3l
AUSUST 16-31
10- - - -
0
YI 20
20
30
3 5
LO
15
S E P T . l - 1 5
-
-
d
5
a
b
c
SUMMARY
10
15
10
25
30
16
4 1
15
SO
WlmW OF HEAD CAPSULE (MICROMETER UNITS)
FIQ. 11. Results of measurements of the width of the head capsule of larvae collected in
the field in 1957 (Both sexes included). The majority of first instar larvae (histogram 1)
originated from eggs collected in the field and reared in the laboratory. The measurements after 15 October are those o f nymphs collected in the funnels described on p. 220.
The bottom graph is a summgry of the others. The numerals 1, 2, and 3 indicate the
histograms of the first, second and third larval instar; 5 denotes the final instar; 4a-c
are explained in the text. One micrometer unit = 0.045 mm.
effect (Weber, 1954; Wigglesworth, 1953). The fraction of individuals
passing through six instars varies from year to year (see p. 258).
The other environmental effects on size will be discussed in the next
section.