-145- 



generation to 17 days in the 13th (Table 3-3). Diets C and D, dubbed 

 "gator grits," are being used in laboratory colonies of four other 

 nearctic sand flies with equally promising results. Since diet C must 

 be incubated, it requires about one month to prepare, while diet D can 

 be prepared in about one day. On the other hand, there is a little 

 more mold growth in diet D and usually more mites. The mold is a 

 problem only with very young larvae and can be easily controlled by 

 adding very small amounts of food at a time. After the first molt, the 

 larvae manage the mold better and the diet can be added in larger 

 quantities. The mite populations can be controlled by autoclaving the 

 diet before use. 



Judging from Figure 3-8, improvements in larval diet had their 

 greatest impact on the 4th instar, which is the largest and, hence, 

 the instar that consumes the most food. It is noteworthy that al 1 

 four larval stages maintained the same order relative to each other 

 but not relative to nonfeeding stages. Under diets C and D, the 

 duration of the 4th stadium was reduced to less than that of either 

 egg or pupa. Under diet E the order of the egg and pupal stages were 

 reversed. 



Diapause and quiescence . Johnson and Hertig (1961) observed 

 extremely uneven rates of hatching time and larval development in some 

 Panamanian species. In Lu. gomezi , Lu . panamensis , and J_u. geniculata 

 (Mangabeira) egg batches, they reported hatching of some eggs three or 

 four weeks after the first hatching, and at least 30 days after 

 oviposition. They concluded that since other eggs in the same 

 cultures had hatched at normal times, culture conditions were probably 

 not involved and some eggs were destined to be quiescent. This is 

 apparently the same type of quiescence observed in many indoor 



