o28 Genus H(«'niapJnjsaJis 



days (Stockinan.s niininmni and niaximum); my observations show a 

 range of 17 days (at 80 C.) to 107 days (at 9° C). The longevity of 

 tlie unfed tick is very marked; the records of Stockman and the writer 

 show that larvae may survive for 803 days, nymphs for 252 days, adults 

 2-i5 days; all stages are therefore able to hibernate readily in this 

 condition. The time which elapses between the dropping of the gorged 

 female from the host and the commencement of oviposition is markedly 

 inthienced by temperature, ranging accordingly from 10 to 211 days 

 (Stockman). Data are lacking as to the duration of oviposition and 

 the number of eggs laid by single females. 



In nature, the tick will probably be able to complete its life cycle in 

 a year l)ut it may well run into two years in our climate. Taking 

 average figures from the data recorded above, the cycle may be completed 

 in 125 days, but the developmental period may of course be much 

 prolonged : 



Time required 

 in (lays 



From the time egg is laid to emergence of larva ... 38 



Larva hardens ... ... ... ... 7 



Larva stays ou host ... ... ... ... 6 



Metamorphosis: Larva to Nymph ... ... 14 • 



Nymph hardens ... ... ... ... 7 



Nymph staj's on host ... ... ... ... 7 



Metamorphosis: Nymph to Adult ... ... 15 



Adult hardens ... ... ... ... 7 



Adult (?) stays on host ... ... ... - 14 



Gorged ? after dropping oiJ host, begins to lay after ... 10 



125 days 



Haemaphysalis cinnabarina. 



This tick requires three hosts upon which to feed as a larva, nymph 

 and adult. The first to raise the tick were Hooker, Bishopp and Wood 

 (1912, p. 98), who state that the larvae feed 5-12 days on rabbits- or 

 guinea-pigs; they twice failed to feed on fowls. Metamorphosis from 

 larva to nymph takes 14 days at 79° F. or 76 days at 54° F. Some 

 unfed nymphs lived up to 55-75 days. Nymphs, placed on cattle, fed 

 for 5-8 days, and then underwent metamorphosis to adults in 26 days 

 at 68° F., or in 186 days at 60° F. (average temperature). Adults 

 survived unfed for 100-805 days. A female (probably unfertilized) 

 lemained foi- 19 days upon an ox; she then (li()p|)ed off replete and 

 survived foi- 172 day.s, bul did not oviposit. 



The following observations were made by me in Cambridge with the 



