February, ’24] jones and bradley: tabanidae of Louisiana 
45 
These records indicate a possible minimum life cycle of a little less than 
5 weeks. 
In cultures begun about the middle of September with wheat har¬ 
vested early in July the usual minimum period from oviposition to 
emergence was about 6 weeks. These trials were made in a laboratory 
kept at living-room temperatures (70 to 80° F.) during the day, with un¬ 
favorable temperatures often obtaining at night. 
The rapidity of development of larvae from eggs laid the same day 
varies considerably. Emergence from eggs laid in August and the first 
3 weeks in September continued, in each case, over a period of about a 
month. During the early part of such emergence the males are the 
more numerous, while near the end the females predominate. 
The sexes occur in nearly equal numbers. Of 6,263 individuals the 
developmental periods of which were recorded, 51.2% were males and 
49.8% were females. The adults have been observed to live for over a 
month, with a maximum longevity of 38 days. Records of 112 mated 
pairs show an average longevity for the males of 12.38 days and for the 
females 13.61 days. 
Table II shows the results of observations on parallel series of mated 
pairs, some of which were provided with drinking water. In the fall 
months the pairs which had water were much the more prolific. Plenti¬ 
ful egg-laying obviously makes heavy demands upon the bodily moisture 
of a female. Further experiments are required to decide the relation to 
fecundity of the moisture content of the grain during immature life and 
of the air humidity during adult life, in the absence of a supply of 
drinking water. 
President A. G. Ruggles: A paper will now be presented by T. H. 
Jones and W. G. Bradley. It will be read by Mr. Bradley. 
FURTHER OBSERVATIONS ON TABANIDAE (HORSEFLIES) 
IN LOUISIANA 
By Thos. H. Jones and W. G. Bradley, Experiment Stations , Louisiana State 
University , Baton Rouge , La. 
Abstract 
The observations here given in brief supplement the reports of Professor J. S. 
Hine and the authors on the Tabanidae or horseflies of Louisiana. One additional 
species has been taken as adult and the larvae of nine species, which had not been 
previously taken in this stage, have been collected in the field. Notes on the time of 
year when adults of various species were taken in the vicinity of Baton Rouge during 
