ROLE OF STOMOXYS CALCITRANS. 



511 



Table XVII. — Sximmarized data of feeding experiments with Stomoxys- 



Continued. 



Time after feeding 

 on infected ani- 

 mals that the flies 

 were applied. 



Num- 

 ber of 

 ex- 

 peri- 

 ments. 



Total 

 number 

 of flies 



used. 



Number and 

 kind of ani- 

 mals exposed 

 to infected 

 flies. 



Nature of experi- 

 ment, or method 

 of applying flies. 



1 



Results. 



6 hours to 67 days. 

 Iday to 28 days.. 



1 day to SO days ... 



Iday to 42 days 



Immediate to 68 

 days. 



30 seconds to 6 

 minutes. 



Immediate 



1 

 1 



1 



1 

 11 



6 



4 



1 



1 



14 

 190 



60 



90 

 23 



24 



48 



25 



75 



61 guinea pigs.. 

 18 monkeys 



8 guinea pigs 

 and 18 mon- 

 keys. 



18 monkeys 



Successive dally 



feeding. 

 Attempts to transmit 



through a cyclical 



development. 

 do... 



Negative. 

 Do. 



Do. 



Do. 



2 positive, 1 to 6 

 hours, 1 imme- 

 diate injection. 



3 positive, all in 

 30-second in- 

 tervals. 



Negative. 



Do. 

 Do. 



do 



12 guinea pigs .. 

 6 guinea pigs . . . 

 4 guinea pigs... 

 1 guinea pig 



Inoculations of in- 

 fected flies. 



Inoculations of soiled 

 proboscides. 



Rubbing infected 

 blood into fly-bitten 

 skin. 



Hereditary transmis- 

 sion, progeny of in- 

 fected flies. 

 do 



80 days to 38 days.. 

 About 26 days 







METHODS EMPLOYED IN FEEDING AND KEEPING FLIES FOR 

 LABORATORY PURPOSES. 



The technique employed in maintaining the normal longevity 

 of Stomoxys applies equally to bloodsucking flies of other genera, 

 for example, species of Lyperosia and of Hippoboscidse. The 

 greatest difficulty was encountered in attempting to keep flies, 

 in either small or great numbers, in a common enclosure. 



Screened stable. — In a screened stable, aside from the artificial 

 obstacle of confinement, the difficulties presented are summed 

 up in the presence of natural enemies, and, do what one may, 

 it is well-nigh impossible to wholly eradicate these. Particular 

 reference is made to the common insectivorous lizard and the 

 ubiquitous spider. Spraying with pure cresol was effective 

 against the individuals present, but the disinfectant did not 

 prevent the entrance of other lizards and spiders. 



Glass vessels. — Large bottles and museum jars of 3 liters* 

 capacity were used when it was desired to confine and to feed 

 at one time large numbers of flies. Thirty days was the longest 

 time flies were kept alive in these containers. In this instance, 



