48 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 1 



and lesser numbers of nymphs to be the habit of the engorged stages 

 to drop during the day time. As mentioned under host relationship, 

 this appears to be a remarkable adaptation to the habits of the host 

 on the part of the tick. It is the habit of the hares and rabbits to re- 

 main during the day time in their resting places, which are commonly 

 kno\\Ti as ' ' forms. ' ' These forms are made by scratching in the grass 

 beneath weeds or brush and furnish protection from the sun and ene- 

 mies, such as the birds of prey. At night they become active, being 

 protected from enemies by the darkness. Thus it is seen that the ticks 

 by dropping during the day time in or near these forms readily find 

 the host after hatching or molting. 



In the genus Ixodes the life cycle of but a single species has been 

 followed, that of Ixodes ricinus by Wheler in England. While there 

 are fourteen species reported from this country, but few have been 

 collected by agents of the Bureau, and these only occasionally. In 

 Florida the writer has found Ixodes scapularis to be quite common on 

 dogs, but because he was not acquainted with the fact that the mem- 

 bers of this genus require more moisture than most other ticks, these 

 died without development. Wheler finds Ixodes ricinus to drop for 

 both molts, as is probably the case with the other species of the genus. 

 He reports the larvae to engorge and drop in two days ; that in winter 

 (February to April) eleven weeks pass before they molt. Of the 

 periods of engorgement of the nymph and adult we are not informed. 

 Engorged nymphs removed May 29 molted three weeks later and an 

 engorged female removed April 15 commenced oviposition on the 27th 

 day following. While this species occurs in this country, it has been 

 taken but once in Texas by agents of the Bureau, although extensive 

 collections of ticks have been made. Immature stages of an undeter- 

 mined species have been taken from the heads of birds by the writer. 



The species of the genus Ambly omnia, the life cycles of three of 

 which (americanum, cajennense and macnlatum) have been followed 

 by the writer and that of the South African species hebraeum by 

 Lounsbury, all appear to drop to molt. The genus is represented in 

 this country by four species, the three mentioned and tuberculatum. 

 Aside from tuberculatum, which has been found only on the land tur- 

 tle in Florida, the species are not closely restricted in their host re- 

 lations. The Lone Star Tick, Amhlyomma americanum, as larvae en- 

 gorge in three days, drop and commence molting eight days later; 

 as nymphs similar periods are necessary for engorgement and molt- 

 ing; as adults eleven days was the quickest period in which engorge- 

 ment and dropping took place. After dropping, at least eight days 

 were found to pass before oviposition commenced. The minimum in- 

 cubation period recorded is for eggs deposited June 25, when 27 days 



