95 



CooLFA- (R. A.)- Notes on little known habits of the Rocky 

 Mountain Spotted Fever Tick {iJcnnacciilor rcim.sfiis, Banks). 

 — //. Ec(jn. Entoiii., vi, no. 1, Feb. lUl-), pp. 9o-9G. 



The characteristic " waiting- attitude '' of this tick is described. 

 The ticks were found to be excited by a sudden interception of 

 the light falling: upon them, and it is suggested that they are 

 made aware of the approach of an animal by this means. 



lluxNTER (»S. J.). Pellagra and the Sand-Fly. — Jl. Ecoii. Enfom., 

 vi, no. 1, Feb. IDFJ, pp. 90-101. 



The author's investigations consisted of a survey of the distri- 

 bution of Sunulium in Kansas, au investigation of their habits, 

 and inoculation experiments. The only species found to be 

 generally distributed over the State is S. oittaturn, the immature 

 forms being found wherever there is trickling water. The species 

 is not confined to clear water, nor even to rural districts. The 

 females oviposit in the evening aud place their eggs on wet 

 leaves in shallow ripples or on rocks, xis the fly oviposits she 

 moves along, stringing the eggs, but holdiug on to the rock above 

 water while the tip of the wings and abdomen are vibrating in 

 the Avater. This process occupies about 10 minutes and 200 eggs 

 are usually deposited. The duration of the egg stage depends 

 somewhat on the temperature of the water, though usually 

 lasting about a week. The length of the larval stage depends on 

 the temperature and rapidity of the water. It varies from 3-4 

 weeks under good conditions, to several months in the overwinter- 

 ing stage. The pupal stage is usually 2-o weeks. The length of 

 the adult's life is not known, though those that have fed on human 

 blood live longer than those that have not. There are two princi- 

 pal broods, one in July and one in October, though some emerge 

 throughout the entire season. The flies appear to scrape the 

 skin till blood oozes rather than to pierce it. The inoculation 

 experiments failed owing to there being no pellagrin available in 

 a proper stage. 



The author's conclusions are that the nnmber of cases of 

 pellagra is proportional to the number of Siinalium; the first 

 appearance of pellagra is coincident with the principal broods; 

 just succeeding the time of the principal broods the flies appear 

 to bite more vigorously ; flies fed on human blood live longer 

 than others, thus favouring au incubation period for a parasite, 

 if such there be; pellagra in Kansas has appeared almost entirely 

 in one district Avhere the flies are unusually abundant. 



On the other hand pellagra has never been induced experi- 

 mentally in any other animal. The appearance of pellagra in 

 Kansas is of recent occurrence and nearly all the cases are those 

 of natives who have never been out of the State. 



