374 
Rhipiceplialus sanguineus 
variability in Set B is considerable, the smallest nymph having a scutum 
only 85% as long as that of the largest nymph iu the same set. 
Measurement in mm. of scuta of unfed nymphs which emerged: 
A, from partly gorged larvae. 
B, from fully gorged larvae. 
No. 
Length 
Breadth 
1 
0-35 
0-42 
2 
0-35 
0-43 
3 
0-35 
0-45 
4 
0-35 
0-46 
5 
0-36 
0-38 
6 
0-38 
0-44 
7 
0-40 
0-45 
8 
0'40 
0-46 
9 
0-40 
0-47 
Average 
0-37 
0-44 
No. 
Length 
Breadth 
1 
0-42 
0-46 
2 
0-50 
0-55 
3 
0-50 
0-56 
4 
0-51 
0-54 
5 
0-54 
0--56 
6 
0-54 
0-58 
7 
0-54 
0-60 
8 
0-55 
0-56 
9 
0-55 
0-58 
10 
0-56 
0-58 
Average 
0-52 
0-56 
Fig. 2. Rhipicephalus sanguineus, nymphs: (1) normally developed unfed individual, 
dorsal and ventral aspects, spiracle and tarsus 4 ; (2) capitulum and scutum of 
nymph which emerged from a partially gorged larva. No. 1932 (8). N. C. del. 
Variation in size in adults. Figs. 3 and 4. 
Measurement in mm. of scutum of 
Set C. Picked in both larval and 
nymphal stages 
Set D. Picked in larval stage only ... 
Set E. Picked in nymphal stage only 
Set F. Normal ticks, i.e. ticks which 
were allowed to gorge fully in both 
larval and nymphal stages 
Normal first cousins to the ticks of 
above series (smallest and largest 
individuals of a large progeny from 
one female). 
Smallest g 
Largest <J 
Smallest 2 
1-20x0-70 
2-0 x 1-30 
0-05 x 0-62 
2-0 x 1-30 
2-50 x l - 60 
0-85 x 0-95 
1-85 x 1-00 
2-30x1-30 
0-80x0-80 
2-30x1-50 
2-60 x 1-70 
1-15 x 1-20 
1-90 x 1-00 
2-60 x 1-55 
l-20x 1-10 
Largest $ 
1-0 xMO 
1-40 x 1-40 
1-15 x 1-15 
1-30 x 1-35 
1-30 x 1-30 
