80 
Psyche 
[June 
Sci., XII, pp. 17-18) also said that this species builds lumps 
of mud, attached to rocks or twigs and of stony hardness. He 
claimed, however, that the cells were stored with insect 
larvae, but he must have made a confusion with the nests 
of some other mud dauber, since Hicks’ observations, re- 
corded below, show conclusively that P. vespoides is a pollen 
provisioning wasp. T. D. A. Cockerell (1913, Proc. Ent. 
Soc. Washington, XV, p. 107) stated that this same species 
was bred by G. Robertson, at Redlands, California, from a 
nest having the shape of an inverted cone and composed 
principally of sand, fastened to the stem of some plant. C. 
H. Hicks’ observations on P. vespoides (1927, Canad. En- 
tom., LIX, pp. 75-79) are much more complete than those 
made on any other masarid wasp. He found that, near 
Boulder, Colorado, the extremely hard mud nests are at- 
tached to rocks. The number of cells varies from 2 to 13 in 
one nest, each cell being about 2 to 3 cm. high ; they are all 
placed vertically side by side, so that the tops, each provided 
with a cup-shaped depression, are in a straight line. A store 
of pollen was found in some of the cells, while others of the 
same nest contained full-grown larvae from which adult 
wasps were bred. It would appear that this species uses 
mass provisioning, since several closed cells were found each 
containing a large mass of pollen. Before pupating the ma- 
ture larva spins a light brown, silky lining over the wall of 
the cell. 
At one time is was believed that some at least of the Ma- 
saridinse might be parasitic wasps, but there is no evidence 
in support of this view. Dours claimed that Celonites was 
parasitic upon Scolia and his supposed observations were 
reproduced by H. de Saussure (1854, Et. Fam. Vesp., Ill, 
pp. 35-36). A. de Winkelried Bertoni (1921, Rev. Soc. 
Cientif. Paraguay, I, p. 11) also stated that his Ceramiopsis 
paraguayensis was parasitic of an anthophorid bee, because 
he saw this wasp entering a vertical gallery in the soil with 
a “mouth-piece” similar to that of Epicharis obscura Friese. 
But the inference is almost certainly erroneous, since we 
know that many masarids that nest in the ground build 
chimneys at the entrance to their galleries. 
