8 
Regeneration in Ticks 
considerable injury. These may remain anchored in the host’s skin, when 
the tick’s body is torn away, and every grade of injury to the mouthpaits is 
observable in ticks that are collected in the field. 
METHODS. 
In all cases the ticks under experiment were operated upon by me as soon 
as practicable, i.e. an hour or two, after they had fed to repletion and had 
dropped off the host. A requisite number having been selected for operation, 
individual ticks were transferred successively to a holder that kept them in 
a convenient position during the brief operation which took place upon the 
stage of a Zeiss binocular microscope. 
The holder consisted of a glass photographic plate of small size upon which 
a band of plasticine adhered. The tick was placed on the plasticine with its 
mouthparts or legs that were to be amputated projecting out over the edge 
of the plasticine, and a second band of plasticine, covered with a piece of fine 
linen, was laid upon the first and pressed down sufficiently to fix the tick in 
position. The tick was therefore held as it were in a vice, a soft one, the gentle 
grip of which could be regulated during the operation and easily readjusted 
if the tick shifted. The piece of linen laid on the plasticine prevented its 
sticking to the operator’s fingers during the manipulations. 
A polished scalpel was held in the left hand with the blade beneath the 
tick’s capitulum (or legs) so that the steel could be cut down upon as on a 
plate by means of a fine needle held in the right hand and ground to an oblique 
chisel edge. Great care was taken to avoid bruising the parts or pulling 
them about and to make a clean cut expeditiously. 
The amputated parts adhered as a rule to the scalpel through the little 
coelomic fluid that escaped from the tick’s wound when the parts were cut, 
rarely did the amputated parts spring away and get lost. They were collected 
after each operation and mounted in balsam as follows: 
A number of slides were prepared by scratching two rows of small circles 
(ca. 6 mm.) upon them with a writing diamond, a circle punched in a piece 
of card and held firmly against the slide serving as a guide to the diamond 
point. The slide was now reversed so that the diamond circles were on the 
under surface and afterwards clearlv visible through the balsam mount on 
the upper surface, on which, at the margin of the slide and close to each 
circle, a number was scratched, the number corresponding to that of the tick 
that was to be operated upon. The slide was cleaned, and a minute drop of 
water was placed over the centre of a diamond circle and brought into focus 
upon the stage of a second dissecting microscope. The amputated parts of 
the tick were transferred on the point of the operating needle to the drop of 
water and this was allowed to dry. When the series of circles was occupied 
by amputated parts and these had dried, a small drop of xylol was placed 
upon them and this was followed by a drop of balsam. Ordinary cover- 
glasses cut in four yielded squares of a size that sufficed to cover the circles. 
