Biology of H. lepoids-pahistris 



535 



15° C, in one case they only emerged after 124 days. Longevity of 

 unfed ticks : larvae survived 258 days, nymphs up to 342 days, a male 

 and female lived up to 403 and 588 days respectively. Oviposition 

 commences 2-18 days after the female has abandoned the host, the 

 process lasting 14-57 days according to the surrounding temperature ; 

 oviposition does not occur at 0^ C. The female dies 0-28 days after she 

 has ceased laying her quota of eggs. The normal number of eggs 

 appears to be 1800-2400, laid at the maximum rate of about 800 in 24 

 hours. 



Hooker states, from personal observation, that large numbers of 

 larvae and lesser numbers of nymphs, when replete, abandon the host 

 during the daytime. He regards this as a remarkable adaptation of the 

 tick to the habits of their usual hosts, the hare and rabbit. These 

 remain during the daytime in their resting places or " forms " and roam 

 at night. The gorged ticks, dropping from the host in the forms, 

 undergo metamorphosis in a situation which favours their finding a host 

 when they emerge and are ready to feed. The observation is certainly 

 suggestive and it would be interesting to learn if other species of ticks 

 behave in a similar manner. The ticks usually attach themselves about 

 the ears and heads of rabbits. 



Laboratory experiments by the authors quoted above (p. 530), 

 indicate that H. leporis-palustris may, under favourable conditions, 

 complete its life-cycle once or twice in a year. This supposition is 

 strengthened by the statement of Hooker, Bishopp and Wood that all 

 stages occur at all seasons upon their hosts in nature in the United 

 States. 



Judging from the foregoing data the life-cycle may be completed in 

 87 to 405 days, as follows : 



From the time the egg is laid to the emergence 



of the larva 

 Larva hardens 

 Larva stays on host 

 Metamorphosis : Larva to Nymph 

 Nymph hardens 

 Nymph stays on the host 

 Metamorphosis: Nymph to Adult 

 Adult hardens .... 

 Adult ( ? ) stays on host . 

 Gorged ? , having dropped from the host, begins 



to lay eggs after ..... 



Totals 



87 



to 



405 days 



