Feb. '08] JOURNAL OP ECONOMIC ENTOMOLOGY 45 



most and is followed in summer by five days before the second molt 

 and the appearance of the second stage nymph. A third engorgement 

 occurs at night (in the latter part of August) and twenty-six days 

 pass before any of the ticks molt and appear as adults. A fourth en- 

 gorgement then takes place, the sexes copulate and eggs are soon de- 

 posited. Unlike the ticks of all other genera, so far as known, these 

 ticks re-engorge a number of times as adults, and the re-engorgement 

 is followed each time by oviposition. The eggs hatch in summer in 

 about fifteen days. The longevity of these ticks and their resistance 

 to insecticides is remarkable. 



The genus Ornithodoros is represented in this country by the two 

 more common species turicata and megnini and two but little known 

 species, coriaceus and talaje. But little is known of the life history 

 of turicata, which Lounsbury suggests as being identical with the Af- 

 rican species savignyi. Ornothodoros megnini, known as the Spinose 

 Ear Tick, from spines of the nymph and its habit of infesting the ear, 

 is a species found frequently in some parts of the South in the ears 

 of cattle, horses, sheep, and a few other animals. The life cycle, which 

 has been followed by the writer, is found to be this : Seed ticks, hav- 

 ing gained entrance to the ear, attach deep down in the folds, engorge, 

 and in about five days molt; as nymphs with their spinose body they 

 appear entirely unlike the larvae. As nypmhs they continue feeding 

 sometimes for months. In experiments made by the writer the first 

 nymph to leave had remained in the ear thirty-five days from the time 

 it entered as a seed tick ; others still remain in the ears at the time of 

 writing (December 7th), a period of ninety-eight days having passed 

 since they entered as seed ticks. After leaving the ears as nymphs, 

 these ticks usually crawl up several feet from the ground and secrete 

 themselves in cracks and crevices, where, in about seven days in 

 September, after leaving the ear, they shed a membranous skin and 

 appear as adults without the spines. Fertilization then takes place 

 and oviposition commences, the female dying with its completion. 

 Unless fertilization takes place, eggs are not deposited and the ticks 

 live for a long period. The incubation period in summer is as short as 

 eleven days. Owing to their habit of remaining for long periods in 

 the ears, they can be carried great distances. This fact may account 

 for their being reported from some of the northern states. 



The second family, the Ixodidce or typical ticks, is represented in 

 this country by nine genera, including thirty recognized and de- 

 scribed, and several undescribed, species. The life cycle of species 

 of the genera Margaropus, Bhipicephalus, Dermacentor, Haemaphy- 

 salis, Ixodes and Amblyomma has been followed. The greater number 

 of these drop to pass both molts off the host. Of the species found in 



