4 FLOWERS AND INSECTS—XXVI 
Generally, determinations of bees are unreliable except when 
both sexes of all of the species are known. When only one sex is 
known the other is probably mixed with that of another species. 
Formerly in Agapostemon four species had been distinguished in 
the females but the males were referred to another species, 
A. tricolor. There was little chance of separating another real 
species and this condition had the advantage of indicating five 
species instead of four. Sometimes the species are separated only 
in the males and the females ignored. Determinations of the 
females are twice as important as those of the males since they 
make twice as many flower visits. 
On account of the impossibility of getting all of the bees identi- 
fied it was necessary to describe the new species and match the 
sexes, thus making a digression which interrupted the study and 
involved an intrusion into a field which there was no inclination 
to cultivate. 
Of all bees the bumblebees are the easiest to collect and identify. 
Eight species occur at Carlinville. Two species, Bombus ameri- 
canorum and Bombias auricomus, had the females mixed under the 
name of Bombus pennsylvanicus and were referred to the male of 
Bombias auricomus, while the male of Bombus americanorum was 
referred to another genus as Apathus? elatus. The female of 
another species was identified for me as Bombus ridingsvi. The 
worker was mentioned in 18, 579, 1891, and the male in 4, 65, 1891. 
But Bombus ridingsii turned out to be a sex name of Bombus bi- 
maculatus, the prior name of the male of the same species. 
From my experience I think that a specialist is competent to 
make determinations, or compare types, only at the time when he is 
making a careful study of a particular group. In 32 cases I re- 
ceived two different specific names for the same insect. 
Your species monger describes the obvious and easy cases, the 
males and females as distinct species, and passes on the difficulties 
to some one else. North America is a large region and entomology, 
or even an order of insects, is a large subject. A specialist’s relia- 
bility bears an inverse relation to the size of the region and the 
extent of the subject in which he affects authority. Students of 
bees describe species from all over North America, and even farther, 
but any one of them, and all of them together, can not identify 
both sexes of the bees of any locality. 
All of the observations given here were made for the purpose of 
ascertaining the different kinds of insect visitors. Collectors’ notes 
are worthless as data of anthecology because the collector is looking 
out for particular kinds of insects and not for all of the kinds which 
