KEEPING AND FEEDING STOMOXYS 367 



It is relatively easy to induce most gravid females of Stomoxys 

 calcitrans to lay their eggs if they are placed in cages either with horse 



manure, straw impregnated with urine and horse 



. . , Breeding technique 



dung, or moist garden manure ; the larvae may be 



successfully raised if the food is kept moist and free from moulds. 

 This is accomplished by placing the cage in the sun for a consider- 

 able time, and adding to it small quantities of water; excessive 

 moisture is to be avoided. In looking for the breeding places of 

 any particular species of Stomoxys attention should be directed to 

 horse dung, stable rubbish, manure heaps in gardens, the banks of 

 streams and marshy ground ; the larvae will be recognized by their 

 characteristic habits when feeding. In Madras on two or three 

 occasions a female has been seen depositing her eggs in a heap 

 of cow dung ; the larvae which hatched out did not, however, reach 

 maturity. 



Mitzmain, in his recent paper on the role of Stomoxys calcitrans in 

 the transmission of Trypanosoma evansi, describes the methods which 



he employed in feeding and keeping the flies alive 



3 ^ . . Methods employed in 



for long periods in captivity. A screened stable was keeping and feeding 



not satisfactory, owing to the large numbers of lizards 

 and spiders which preyed on the flies ; it was found impossible to 

 prevent these from entering the stable. The writers found the same 

 difficulty when experimenting with some species of Tabanus. Large 

 bottles and museum jars were used by Mitzmain to confine and to 

 feed large numbers of flies ; the jar he figures is very similar to the 

 one used by the writers (page 343). The longest time the flies were 

 kept alive in these receptacles was thirty days ; it was found advisable 

 to transfer each fly to a single test tube after each feed towards the end 

 of this period, about the twentieth day. As in the case of Glossina 

 (see further on), it is difficult to prevent an excess of moisture collecting 

 in the jars, even though a large quantity of filter paper is used. The 

 large quantities of faeces passed by these flies and the condensation 

 of moisture in the jar or bottle soon results in the early death of 

 most of them ; for this reason only a very few flies are placed in each jar. 

 Mitzmain also found that cannibalism was common. If a fly was in any 

 way disabled, especially after a recent meal, another active one attacked 

 it, puncturing its abdomen. Mite infestation, which is common on 

 most muscids, was also a serious hindrance when large numbers of 

 flies were kept in the jars. 



The best results are obtained by keeping each fly in a glass tube, 



