1923] 
Flower Visits of Insects 
163 
Labiatse and 35.7 to Compositse. Before July they prefer Ma, 
Mas and red; after June, Mas, red and yellow. The maxima 
shift from Hb 68.9 to B' 49.0, Ma 56.1 to Mas 64.4. 
Xyloco'pidce. — The single species, Xylocopa virginica, near 
its northern limit here, is rare and its visits few. It seems to 
prefer Mas and red. 
Ceratinidce.—Oi 194 visits to 162 flowers, 33.5 per cent are 
to Mis, 27.8 to Mi, 21.1 to Mas, 47.4 to white and 24.7 to Com- 
positse. The visits of the males differ remarkably from those of. 
the females and under similar conditions. The females show Mi 
22.4, Mas 30.4, Mis 23.2 and red 32.5. The males show Mi 42.8, 
Mas 3.0, Mis 40.8 and red 14.2. In their visits they resemble 
the Halictidse and Apis mellifera. Before July they prefer Mis, 
Mi, Pol, and white; after June, Mas, Mis and red. The maxima 
shift from AB 28.4 to B' 55.2, Mis 35.3 to Mas 52.2, white 50.7 
to red 37.3. 
Melectoidea (ex. Nomadidse; 209 visits to 72 flowers). — 
These prefer Mas 67.9, Mis 25.8 and yellow 41.1. Fifteen prefer 
Mas, five Mis, one Ma, ten yellow, six red, six white. Of the 
visits of Epeolidse 15.6 per cent are to Labiatse and 58.5 to Com- 
positse. 
Nomadidce. — Of 272 visits to 108 flowers 48.5 per cent are 
to Mis, 31.9 to Mi, 51.1 to white, 36.3 to yellow, 14.7 to Com- 
positse, 14.3 to Salix and 11.7 to Bosacese. Being inquilines at 
least principally of Andrenidse they are associated with them in 
time and place and naturally show similar flower visits. Sixteen 
prefer Mis, four Mi, two Mas, 14 white, nine yellow. 
Melectoidea the 481 visits, 38.6 per cent are to Mis, 
33.4 to Mas, 41.7 to white and 38.4 to yellow. The Nomadidse 
make only 17 visits after June, and the other Melectoidea make 
only five visits before July, so that their differences are largely 
phenological. Before July they prefer Mis, Mi, yellow and 
white; after June, Mas, Mis and j^ellow. The maxima shift 
from AB 32.6 to B' 58.9, Mis 45.7 to Mas 66.0, white 50.5 to 
yellow 39.6. 
Megachilince. — The Megachilini (331 visits to 151 flowers) 
prefer Mas, Mis, red 40.1 and yellow 33.3. The flowers visited 
