jrom the Rio Nautla, State of Vera Cruz. 285 
second segment are obsolete, as in Williston’s specimen from 
St. Vincent. No reliance can be placed on the character of 
the apical cell being petiolate, nor can the extent of the pollen 
on the abdomen be relied upon. These forms might be con- 
sidered varieties, though it would be hard in that case to 
decide where to stop defining varieties and recognize mere 
individual variations. 
C. propingua, Wulp, if a female as designated, is at least 
a good variety, bearing the same relation to occédua that 
exists between ¢mmaculata and Pallasti. But the colour of 
the antenne and palpi is of comparatively no importance. 
C. griseonigra, Wulp, is probably a variety of Pallasit. 
But it is useless to speculate on descriptions not exceeding 
two to four lines, except in so much as they indicate what is 
still to be found and described. I will not attempt an ex- 
amination of Wulp’s male Cistogasters, which all seem easily 
referable to either occidua or immaculata, though, of course, 
nothing can be said of them in their present incompletely 
characterized state. It is greatly to be regretted that such a 
long delay, though doubtless unavoidable, in the appearance 
of the parts of the ‘ Biologia Centrali-Americana ’ should have 
caused the publication separately of such short diagnoses of 
species. ‘The diagnoses, if presented separately in advance, 
should be full and complete. 
It may be noted here that Cistogaster is another of those 
tachinid genera which are not at present known to occur in 
New Mexico. 
» 
Phaniide. 
44, Xanthomelanodes arcuata, Say. 
Four males and four females. Paso de Telaya, one female, 
March 28, and two females, April 7. San Rafael, one female, 
June 20, in sweepings. The males, all San Rafael, on flowers 
of the Cordia sp., June 29 and July 5, 12, and 16. 
Length of males 5 to 7 millim., of females 5 to 6} millim. 
The allied X. atripennis was described by me in Notes 
N. Amer. Tachin. 1. pp. 145-146, as a Wahlbergia. The 
latter genus should be knownas Besseria. ‘The present forms 
are very distinct from Besseria, lacking entirely the peculiar 
female abdominal characters of that genus, besides differing 
widely in other respects. 
The present specimens of arcuata vary considerably in 
size, two of the males (July 5 and 16) and two of the females 
(March 28 and June 20) measuring only 5 millim.; but they 
hardly differ in coloration, and are without doubt all the same 
