BY C. J. POUND, F.R.M.S. 35 



weeks, while in other cases the apparent shock to the system of 

 the tick was so great that the process of oviposition was suspended 

 altogether, and the ticks died. 



During the winter months the period of time occupied in 

 the laying of the eggs and their incubation varies considerably. 



As the exact nature of the material with which the eggs are 

 coated has not been determined, it is interesting to know that it 

 posseses the property of retaining its viscidity for a very long 

 time (many weeks, in fact) without becoming hardened by ex- 

 posure to the air ; so that if the eggs are put separately into a 

 bottle and the latter shaken, the eggs readily become aglomerated 

 into a ball by contact with each other. 



A most noticeable feature during the process of oviposition 

 is the deepening in colour of the yellow bands which just before 

 the death of the tick Ijecome a brilliant orange. 



A fully-developed tick will lay from 1,800 to 2,000, and 

 sometimes 2,300, eggs, each of which is about one-fiftieth of an 

 inch long and one-seventieth of an inch broad. They are bluntly 

 oval in shape, of a light brownish colour, and vary in size 

 according to the mother tick. For instance, several female ticks 

 were remove<l from the skin of an animal before they were half- 

 grown ; these laid eggs, pale in colour, mostly very nuich smaller, 

 compared with normal eggs ; moreover, with few exceptions, 

 instead of hatching, they collapsed, and eventually withered up, 

 from which it might be concluded that the female tick was 

 imperfectly fecundated. 



The vai-ious changes which the egg undergoes before hatch- 

 ing can be watched under the microsope, the outer membrane, or 

 shell, remaining almost transparent till the young tick is fully- 

 developed, when, within four to six days before hatching, the 

 shell gradually Ijecumes opaque-looking, like a small pearl. 



On emerging from the egg, the larvae, which are very minute 

 creatures, have only six legs, and are of a peculiar brownish, 

 translucent, waxy colour. The pulvilli, or foot pads, on the 

 anterior pair of legs are very much larger than those on the 

 second and third pair of legs ; in fact, altogether the first pair 

 of legs exhibit a higher development than the remainder. 



