336 ENTOMOLOGICAL ne;ws. rjan 



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. 



LIFE HISTORY OF A TICK. 



The scantiness of the i^resent knowledge of the life history and 

 habits of the tick kind may render the following observations on 

 the South African BontTick Amblyommahebroium 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 iu 

 pastures. 



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

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

 young tick ascends the nearest support, 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 and attached, 

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

 diriteution 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 tive to 

 eight days in the thousands of larva' 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 difl'erence in the flow of blood from dirt'eront 

 tisRties. 



The distended larva Is very active until a place for (Concealment is 

 found. Then it bectomes Hluggi^ih and gradually dormant. After a 

 perlo<l of variable length the skin ruptures across the front and the 

 nym])li stage begins. If the ti(r|^ is kept contiiuially in a temv)era- 

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

 plete in sixteen days from the voluntary dropping, rndcr ordinary 

 conditions of temperature, however, the pericxl \\n\A be a long one; 

 in the case of some of the ti<kM reared it cxceedc;! eleven weeks. 

 The nymph l)cliaveH mii(;h an did the larva, but, naturally, ai^ it is 

 separated from its brothern, it generally waits alone, in time it 

 UMUttlly •ccures a hoot. Then, as before, there is litt le change in size 



