1 Ava., 1901.] QUEENSLAND AGRICULTURAL JOURNAL. 261 
When the tick is lying on its back only two rows of teeth are seen. Above, 
and a little to one side, are the chelicéres (sheaths) longer than the dart and ter- 
minating in two articulated fingers—one long and delicate, with two teeth, and 
situated on the inside ; the other shorter and stouter on the outside, and likewise . 
furnished with two teeth. 
Above the sheaths is a transparent web-like attachment, terminating in a 
spatula at its free end, and having on its upper surface short spines, which give 
it the appearance of a rasp. This sort of upper lip is in the shape of a gutter, 
and quite encloses the sheaths. On each side of the members mentioned there 
are papille, abundantly furnished with hair or spines. 
The dorsal shield descends a little lower than the last pair of legs. On the 
body, which is covered with undulating streaks, are to be seen some small spines. 
On the back, on the median line, towards the posterior third of the body, the 
anus is surrounded with another web-like structure, but rounded. 
The young larve were examined every day ; they grew very quickly. On 
the 15th, that 1s to say, seven days after they had been placed on the bullock, 
one of them measured 1 m.m. 45 in length and 0 m.m. 80 in breadth. On the 
16th some of the ticks cast their skin for the first time, and are now at the 
stage of octopodian nymphae, for now they have four pairs of legs. They also 
differ from the larve by the appearance behind the last pair of legs and on 
both sides of the body of a stigmatic plate surrounded by a circle of web-like 
appearance as described above. (Plate X., Fig. 3.) 
Lastly, if we examine the proboscis, on the ventral side, we find it enlarged 
and on each of the barbs of the dart may be counted three rows of teeth 
instead of two. Measurements of the Nymphe :— 
: . Length, 1 m.m. 40 
1. On first casting the skin { iyaatab, (sania, 6 
, Length, 2 m.m. 62 
Breadth, 1 m.m. 76. 
= After the first sloughing, ticks may be observed whose shield is small, and 
the ‘ovoid abdomen much elongated; in others, the shield and rostra are 
broader, the abdomen narrower, the body covered with stronger spines, and 
the dimensions much smaller. I give here the measurements of one of these 
last nymphes, five days after the first sloughing— 
Length ... oo on eH eno 1 svaiginy, Cs 
Breadth ... aes om er ... Om.m. 70 
The ticks which have performed their first sloughing fasten themselves 
afresh quite close to the spot to which they were first attached. Very soon, 
small pretty rosy rings are seen to be formed round the puncture, on the skin 
which is deprived of hair. 
On the 22nd, the ticks begin to take on a russet-brown colour; it is still 
difficult to find them on the skin, unless they are very numerous. On the 
backs of some there are several longitudinal rays. 
On the 26th, the ticks sloughed for the second time, and the sexes are then 
disclosed. ‘The males come forth first, and fix themselves by their rostra on 
the very spot were the second sloughing was effected. 
After this sloughing, the legs appear longer. The rostrum has thickened - 
it possesses the same characteristics as in the larve, but there are four pairs of 
Heeth visible on the dart, instead of three, as in the nymph, and two as in the 
rva. 
Dimensions of ticks immediately after the second sloughing :— 
Length ... ©... 2m.m.20male ... 3 m.m. 25 female 
Breadth ... .. lmm.40male ... 1mm. 70 female 
The: male, which is very active, is easily recognised. At the posterior 
part of the body may be seen a small prolongation, which is no other than the 
penis; on the ventral side, and immediately in rear of the rostrum, is a 
transverse crack surrounded by a bundle of spines. The shield covers the 
whole upper part of the body, which is amply furnished with sharp spines. 
2. Five days afterwards 
