Cooper and Bequaert — Records of Masarid Wasps 139 
1950, at Penstemon unilateralis (R. R. Dreisbach) ; flower deter- 
mined by Dr. F. W. Pennell; both 2 and $ very numerous while 
the sun was shining, visiting the flowers; none were at the flowers 
while it was cloudy. 
This species is one of the most widely distributed of the genus, 
being known at present from Oregon, California, Nevada, Wyoming, 
Idaho, South Dakota, Utah, Colorado, Nebraska, Arizona and New 
Mexico. Its true foodplants appear to be several species of Penste- 
mon, as discussed elsewhere. In this connection, Cresson (1864) 
states that Ridings collected Ps. vespoides near Empire City, 
Colorado, at flowers of “a plant allied to the genus Lobelia, grow- 
ing abundantly on the roadsides.” This was evidently a Penstemon . 
The extent of the yellow marking varies greatly. Females from 
California are often more yellow than those from Colorado, some- 
times even showing short yellow longitudinal streaks on the meso- 
notum before the scutellum. Some females are nevertheless practical- 
ly colored alike in both geographic regions, so that it does not seem 
possible to segregate the very xanthic specimens as a distinct geo- 
graphical subspecies. Moreover the specimen with the greatest 
extent of yellow is a female from Arizona (White Mesa, Kayenta), 
which not only has very wide abdominal bands, but also has most 
of the pronotum, scutellum, postscutellum, propodeum and pleura 
yellow, curved yellow lines along nearly the entire notauli and 
side lines near the tegulae on the mesonotum. Such extreme var- 
iants are very similar to Ps. wheeleri. If the need were felt for a 
special name, they should be called var. robertsoni Cockerell. 
2. Pseudomasaris ( Pseudomasaris ) marginalis (Cresson) 
Colorado: Moraine below Hill’s Mill, 9,800 ft., 1 $ at Phacelia 
heterophylla Pursh, 10 AM, July 27 (KWC) ; Rainbow Lakes, 
10,000 ft., 3 $ and 2 $ at Phacelia heterophylla, 9 AM to 2 PM, 
July 30 (KWC); vicinity of Science Lodge, 9,500 ft., 1 2 sunning 
on open, sandy bank of road, 9:25 AM, Aug. 5 (KWC); Sierra 
Blanca (L. Bruner) ; Ute Creek (L. Bruner) ; Cascade Lodge, 
Rocky Mountain National Park; Echo Lake, 12,000 ft., 1 2 (R. R. 
Dreisbach and R. K. Schwab). 
Utah: Bear River, North slope of Uinta Mts., 8,000 ft., 2 $ 
and 3 2 at Phacelia sericea (Graham) Gray, June 27, 1949 (F. 
Werner and W. Nutting). 
Known from British Columbia, Alberta, Utah, Colorado and 
New Mexico. The food plants are species of Phacelia. 
