The Ohio Naturalist. 
[Vol. V, No. 2, 
2 24 
fully considered heretofore in connection with species most like 
it it is included, 
Chrysops lupus Whitney. Resembles proclivis, furcatus and 
coloradensis. The frontal callosity, the facial callosities outside 
of the sutures and a band on each cheek are black. Abdomen, 
black, arranged almost as in jjroclivis except there is no small 
black dot on either side of the second segment and the third and 
fourth segments have the l)lack more distinctly in the form of 
spots necessitating more yellow and consequently making the 
whole abdomen appear lighter in general coloration. The tvpe 
was collected in Colorado and specimens are before me from 
Laggan, Alljerta, collected by Professor R. C. Osburn. 
Chrysops mitis Osten Sacken. Much like carbonarius. In 
fact there is some doubt whether or not it should be considered 
as distinct from that species. The absence of a hyaline spot at 
the base of the fifth posterior cell and the somewhat larger size 
separate mitis from its near relative. 
Chrysops nigripes Zetterstedt. Loew first re])orted this spe- 
cies from Alaska and Coquillett recognized a specimen taken by 
Kincaid of the Harriman expedition. This latter specimen is the 
only one that I have seen, for it appears to be difficult to get even 
European examples. The union of the apical spot and cross- 
band seems to l)e the best means of separating it from noctifer 
its nearest American relative. 
Chrysops noctifer Osten .Sacken. I have seen the tvpes of 
both Cilsten Sacken and Williston and cannot see how it is possible 
to recognize the two s]>ecies noctifer and pertinax. The dift'er- 
ence in the two descrijjtions is mainly found in the presence or 
absence of reddish on the sides of the first two abdominal seg- 
ments, and this appears to be too variable to be of specific value 
1 believe the two names are synonymous, and as noctifer is the 
older, it must be retained for the species. The prevailing black 
color of the whole body, and the apical spot separated from the 
cross-l)and are characteristics. 
Chrysops pachycera Willison. Dr. Williston’s types, a fine 
series of specimens from Dr. F. H. Snow and collected by him 
and his associates in Arizona and other specimens collected in 
Lower California have given me the opportunity for studying this 
species. 
The first antennal segment is swollen, the third segment is 
much longer than the second, the facial and frontal callosities are 
yellow. In both sexes the anal cell is hyaline at base and the 
yellow on the sides of the first four abdominal segments is more 
extended than in related species. 
Chrysops pikei Whitney. This recently described species has 
affinities with sequax and univittatus. The first basal cell is 
infuscated with the exception of a small elongate hyaline spot 
