these early field and laboratory workers, Cunliffe observed a 

 female that produced a lifetime total of 535 eggs of which over 

 ninety percent were fertile. In Jobling*s tests, one female 

 deposited several batches totalling 1,217 eggs and eight other 

 females laid totals of from almost 700 to over 1000 each. Dr. 

 G. E. Davis and Dr. W. Burgdorfer report (conversation^ that the 

 largest number of eggs they have observed in a single oviposition 

 has been 233 and 327, respectively. Most eggs are laid at night 

 and sometimes more than one day is necessary before a full batch 

 is deposited. 



Six or seven batches, gradually diminishing in numbers, ap- 

 pear to be usual in one female's lifetime. The amount of the 

 previous blood meal influences the number of eggs subsequently 

 produced. Jobling noted that the fertility of later batches de- 

 creases. 



In a laboratory study of 0. moubata fertility, Robinson 

 (l9A2Cj found that three egg batches may be laid after one mating 

 but that egg fertility is considerably increased if mating occurs 

 before each oviposition. Fertility decreases when the interval 

 between mating and oviposition is extended. Oviposition occijrs 

 almost without exception only after a blood meal. Eggs show no 

 alteration in fertility when maintained between 22°C . and 32°C . , 

 but at 34-°C. no larvae emerge. /~As already stated. Lees and Bea- 

 ment (l9/k8^ have stated that A5°C. is the critical temperatvire for 

 normal eggs. 7 Robinson recommenced a temperature of 30^. and a 

 relative humidity of 50^ in the breeding chamber for safe and 

 speedy production. He found that a female might deposit a few 

 eggs without a blood meal aJid that large females produce more 

 than do small ones. The range in number of eggs per female per 

 batch in these experiments varied from fifty to 250, with an av- 

 erage of 170. Many females died shortly after their first blood 

 meal; others after depositing their first egg batch. 



According to Robinson, females lay over twice as many eggs 

 when sand rather than a flat surface such as filter paper is pro- 

 vided for this purpose, but Dr. G. E. Davis and Dr. W. Burgdorfer 

 report (conversation) that in their experience the opposite is 

 true. 



- 137 _ 



