44 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. xxviir. 



Pllll.rS ANNri.ATl'l 



and is then in a niaturo condition. The life history of ticks has been 

 described by Curtis, ^Morgan, Lounsbury, and othtn-s. Ticks pair 

 during- parasitism, the male remaining beneath the female for some 

 days, the latter finally dro})ping' to the ground to deposit her eggs. 

 These may be as many as 1< »,()()(> to 20,0()(>, and issue as elongate 

 masses in fi'ont of the tick. During the operation the head is with- 

 drawn into the ])ody, so that the 

 neck behind the capitulum is close 

 to the genital poi"(\ As the eggs 

 issue they are coated with a yis- 

 cous substance secreted from 

 glands in the neck. These eggs 

 lay upon the surface of the soil, 

 or just l)eneath it, and the laryi\3 

 hatch in a few days. The young 

 ticks, known as '• seed ticks," 

 ascend the nearest support of 

 grass or herb, and patiently await 

 the comingof some animal. Dela}^ 

 and disappointment nuist often end in staryation and death. How- 

 eyer, many secure an attachment to some animal, often, perhaps, not 

 the desired one. In a few days the young tick is rapidly distended by 

 the blood it has sucked from its host, and drops to the ground. Here 

 it seeks a cayity or hiding place, and rests. In three or four days 

 the skin splits and from it the nymph issues, and l)egins the same 

 waiting process that it experienced as a larya. As it has already had 

 a good meal of blood, it can wait 

 for many days without fear of 

 death. Wh(Mi it secures hold of 

 an animal, the a))domen distends 

 as l)efore, and it soon falls off 

 again to hide and molt. After 

 this molt the tick is adult; it waits 

 again fora host, and when secured 

 starts the life-cycle anew. The 

 Texas cattle-tick and its allies do 

 not drop off for molting. l)ut cast 

 the skin while upon the host. 

 They drop to the ground, howeyer, for the purpose of laying eggs, 

 as the other ticks. 



In the true ticks there is a considerable difference in the abdomen 

 of males and females. In the latter the dorsal shield does not coyer 

 the entire abdomen, while in the male this shield extends to the tip. 

 The males of some species haye spines upon some of the coxa?, and 

 sometimes an extra pair of shields on the yenter. 



Fk;. 75. — Larv.v of BoopHiLt's anntlatus. 



