aT he 





















lulah, La., state: "The winter of 1932-33 was unusually severe. Never— 
theless a remarkably large proportion of the nymphs survived. pre 
portion of survivors among those that were more than half grown in 
fall was much greater than among those less than half grown at t 
time." Of 400 nymphs that were more than half grown in the fall eee 
or 56.25 percent, had survived when counted on April 7. Among these 
were 7 adults--4 males and 3 females. Of 400 nymphs that were less 
than half grown in the fall, 58, or 14.5 percent, survived, including 
1 adult male ard 2 adult females. The total survival for the 800 nymphs 
of all sizes was 203, or 25.35 percent. 7 
etn 
Cotton flea hopper investigations.--The workers at the new labo— 
ratory established this spring at Port Lavaca, Tex., for investigations 
of the cotton flea hopper (Psallus seriatus Reut.) are devoting consid— 
erable attention to the study of wild host plants. This mirid passes _ 
the winter in the egg stage in the stems of cotton and a number of weeds, — 
the most important of which is Croton spp. Upon hatching in the spring 
they feed and breed on numerous species of weeds and migrate in enormous © 
numbers to the cotton field later in the season. Horsemint (Monarda sp.) — 
is probably the most important spring food plant in that section. The — 
unusual abundance of wild host plants for fall oviposition and spring 
feeding forms a combination of favorable conditions which cause the flea 
hopper to be the most important cotton pest in sections of eastern Texas, - 
K. P. Ewing and R. L. McGarr report that during April a total of 37,221 
nymphs emerged from 32 hibernation cages in each of which were placed 
JCO plants last fall, as compared to 38,578 for March and 218 for Feb- — 
ruary. From February 14 (date when hatching started) to April 30, 76,017 
nymphs emerged from plants under observation, 61.2 percent of which were 
within a 6-day period--from March 29 to April 3. The maximum number tom 
date fora single day was on April 1, with 13,204 nymphs, and the minimum 
was on April 29, when only 2 nymphs were found. During the latter part of | 
April an average of 1,153 adults and 8 nymphs (per 100 sweeps) were swept — 
from horsemint, 167 adults and 88 nymphs from croton, and 7 adults and 
no nymphs from cotton. In April oviposition was taking place on the fol-— — 
lowing four plants listed in order of importance: Horsemint, croton, 
butterweed, and primrose. Sticky flight screens have been set up anda 
Systematic sweepings of cotton plants are being made to determine migra— 
tion from wild hosts to cotton. " 

a Me 
oe vee 
INSECTS AFFECTING MAN AND ANIMALS 8 










Sand fly larvae (Culicoides) are scavengers.——-W. FE. Dove, Savannah, 
Ga., reports: "Our experiments show that sand fly larvae of salt marshe * 
ere scavengers, * * * Culicoides larvae developing in rot holes of trees 
are scavengers. The salt marsh larvae feed on decaying fish and worms | 
killed by the salt of the tidal waters. Much of the fish carrion is af- 
forded by the trapping of minnows and the drying out of. water in de— 
pressions and pockets of the marshes. As these places become dry the 
minnows die, decay slowly, and become food for sand fly larvae. In 
rot holes of trees, Culicoides larvae are favored with nature's insect — 
