'42 



tiofo, and perhaps is of unrivaled dimensions. The American cattle 

 tick is a mere pigmy in com,parison. The bont female measures up 

 to an inch in length, three-fourths of an inch in width, and half an 

 inch in thickness. After engorgement she drops from her host and 

 secretes herself. In soft sand she may burrow an inch or two down- 

 ward, while in harder soil or in rubbish she may rest content after 

 bur3dng the forepart of her body. She lays her eggs in a compact 

 mass anterior to herself in this retreat and dies at her post after the 

 completion of the task. Exceptionally large females probably deposit 

 as many as 20,000 eggs; a careful estimate on one batch of eggs 

 obtained in confinement placed the total number at about 17,500. 

 Oviposition, incubation, and all the other periods in the life cj^cle off 

 of the host vary in duration with the temperature of the surround- 

 ings. Development in these stages proceeds all through the year, but 

 is many times more rapid in summer than in winter. The winter 

 season in the area infested is mild and dry. without snow and with but 

 few hard frosts. The j^oung ticks ascend the grass, bushes, or other 

 support above them and there patiently await a host. The passage of 

 animals in their vicinity, by means not yet satisfactorily determined, 

 arouses their attention and incites them to run about clawing the air 

 with their forelegs. Attachment to a passing object is secured by the 

 waving legs, but a large proportion of the tiny creatures are brushed 

 off again almost immediately. Such unfortunates must, perforce, 

 await other opportunities. If the passing object prove a host those 

 that contrive to maintain their hold soon find the skin and inserting 

 their rostra proceed to gorge themselves on the blood. The opera- 

 tion of engorgement ordinarily requires about six days. Except as 

 regards the duration of the difi'erent periods, the habits of the bont 

 tick from the dropping of the female to the engorgement of the larva 

 coincide with those of the American cattle tick; thereafter, however, 

 there are differences. The bont larva when replete with l^lood with- 

 draws its rostrum, drops from the animal and undergoes its metamor- 

 phosis in hiding on the ground. Sixteen days or longer, according to 

 the temperature, pass before the larval skin ruptures and the eight- 

 legged, flat-bodied nymph appears. The nymph seeks a host not alone 

 through patient waiting and waving of its claw-armed forelegs but by 

 running about on the ground when an animal is near. Engorgement 

 is again completed about the sixth day and the tick then bears a super- 

 ficial resemblance to the gorged female of the common cattle tick; it 

 is, how^ever, shorter and relatively broader and of a different shade of 

 blue. Voluntary dropping and, after an interval of eighteen days or 

 longer, a second molting follows. The tick has then reached the adult 

 stage. The sexes, which were indistinguishable in the earlier stages, 

 may be told at a glance when adult. They have similar dimensions, 

 but the markings and colors are dissimilar, and the shield of the male, 



