336 ENTOMOLOGICAL NEWS. [Jan 



DEPARTMENT OF ECONOMIC ENTOMOLOGY 



Edited by Prof. JOHN B. SMITH, Sc. D.. New Brunswick, N, J, 



Papers for this department are solicited. They should be sent to the editor, 

 Prof. John B. .Smith, Sc. D., New Brunswick, N. J. 



LIFL HISTORY OF A TICK. 



The scantiness of the present knowledge of the life history and 

 habits of the tick kind may render the following 4 observations on 

 the South African Bont Tick Amblyommahebraxcm Koch of some in- 

 terest to American students. Other species found at the Cape pre- 

 sent a similar life history, and the same is doubtless true of some of 

 the American species, as, for instance, the Lone Star Tick and the 

 Dog- Tick of the South, which Professor Morgan, of the Louisiana 

 Experiment Station, states are to be found as nymphs and adults in 

 pastures. 



The mother Bont Tick deposits her eggs on or in the soil or in 

 rubbish, by preference just beneath the surface iu soft ground. The 

 young tick ascends the nearest sxipport, whether grass, bush, fence 

 post or anything else, and there, in company with its kind, awaits 

 the passing of an animal. It generally remains motionless, but a 

 movement in its vicinity usually causes it to extend its fore legs 

 and to vigorously claw the air; this admits of its securing a hold 

 on an animal with little waste of energy. Once on iand attached, 

 little enlargement takes place until after the third day. Then rapid 

 distentiou occurs, and in a day or two the tick lets go its hold and 

 drops. The duration of this period on the host varied from five to 

 eight days in the thousands of larva 3 reared in the course of recent 

 studies; the greatest number always fell on the sixth day. The 

 reason for the variation is unknown, but is suspected to be con- 

 connected with the difference in the flow of blood from different 

 tissues. 



The distended larva is very active until a place for concealment is 

 found. Then it becomes sluggish and gradually dormant. After a 

 period of variable length the skin ruptures across the front and the 

 nymph stage begins. If the tick is kept continually in a tempera- 

 ture of ninety degrees or above, the change to the nymph is com- 

 plete in sixteen days from the voluntary dropping. Under ordinary 

 conditions of temperature, however, the period must be a long one; 

 in the case of some of the ticks reared it, exceeded eleven weeks. 

 The nymph behaves much as did the larva, but, naturally, as it is 

 separated from its brothers, it generally waits alone. In time it 

 usually secures a host. Then, as before, there is little change in size 



