46 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 1 



this country Margaropus annulatus and Dermaccntor nitens pass both, 

 molts on the host and a species of Haemapliy satis, found in Texas, 

 liousiana and Florida upon birds, has been determined by the attached 

 molted skins to pass at least the first molt upon the host. In the 

 species which molt upon the host, molting: closely follows engorgement, 

 but in the species which drop to molt there follows a quiescent period 

 •of two weeks or more. 



All species of the genus Margaropus, so far as known, pass both 

 molts upon the host. The single species of the genus found in this 

 country, annulatus, attaches to cattle, horses, mules, donkeys, deer, 

 and occasionally to sheep, goats and dogs. The larvae following at- 

 tachment engorge to repletion and molt in six or seven days; then 

 follows a similar period of engorgement as a nymph and another molt. 

 Appearing as an adult, the male searches out the female, and copula- 

 tion continues until the engorged female drops, which may be as soon 

 as five days after molting. In summer deposition commences in three 

 days after dropping and an incubation period of twenty-one to twenty- 

 five days follows. 



Most species of the genus Rhipicephalus pass their molts off the host, 

 as is the ease with the species found in this country. Lounsbury, how- 

 ever, has found that a South African species, Rhipicephalus evertsi, 

 passes the first molt upon the host. The Brown Dog Tick, an un de- 

 scribed species near sanguineus and the sole representative found in 

 this country, engorges as a larva and drops in from three to seven 

 days following attachment. A quiescent period of twenty days as 

 the minimum was found to be passed at Dallas in October before molt- 

 ing commenced. As nymphs a period of engorgement of four days or 

 more is passed before dropping occurs; this is followed by a qui- 

 escent period of fourteen days in October, when molting commences. 

 As in Margaropus the male searches out the female and remains in 

 •copula until she drops, engorgement of the adult female taking about 

 a week. Deposition of eggs commences in three or four days after 

 dropping. At Dallas eggs deposited May 17th commenced hatching 

 in twenty-five days. The usual host of this species is the dog, so far 

 as is known, no records of other hosts having been made. 



In the genus Dermacentor we find species of the two classes, i. e., 

 those which drop for both molts and those which pass both molts on 

 the host, the first represented by occidentalis and variahilis and the lat- 

 ter by nitens. Doctor Rieketts has determined this habit in occi- 

 dentalis from material collected in Montana and has furnished some 

 additional data on their habits.* He reports horses and cattle as 

 hosts in Montana. It has been determined by the writer at the 



"■Journ. Amer. Med. Ass'n, p. 1069 (Oct., 1907). 



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