34 6 
Psyche 
[June 
Curiously, we found none of these Sarcophaginae in any of the 
study areas in Argentina. One fly noted trailing a Rubrica that was 
digging in a road near Yacochuya proved to belong to the genus 
Senotainia , of the Miltogramminae. One of 14 cells excavated at this 
locality contained 2 small maggots in debris surrounding a cocoon, 
but we did not rear these successfully. Brethes and Llano made no 
note of inquilinous flies in eastern Argentina, and Brethes noted that 
the cells he excavated contained little in the way of debris, doubtless 
the result of cell cleaning. 
A minute fly of the family Chloropidae, Liohippelates pusio 
(Loew), was also recorded by Vesey-Fitzgerald (1940) in asso- 
ciation with R. surinamensis in Trinidad. This fly has also been 
observed at St. Augustine in the immediate neighborhood of nests 
and also entering open burrows in the absence of the wasp. This 
fly is no doubt also a nest scavenger, and its larvae probably feed on 
the uneaten remains of prey left by the wasp larva. 
Structure of Cocoon 
Ten cocoons of R. surinamensis were collected at Cali, Colombia, 
2 more near Cafayate, Argentina. The cocoons from the two lo- 
calities are very similar, and the following notes pertain to all 12. 
The cocoons are ovoid, more pointed at the posterior end, and have a 
hard wall made up of soil particles and salivary secretions, as usual 
in Bembicini. They vary in length from 25 to 28 mm (mean 26.7 
mm) and in maximum width from 8.5 to 10 mm (mean 9.6 mm). 
The pores are more or less evenly distributed around the widest part 
and number from 4 to 6 (actually 5 of the cocoons we collected have 
4, 4 have 5, and 3 have 6). Each pore is complex, being darkened 
and strongly elevated, some of them rising as much as 0.4 mm above 
the cocoon surface; each is somewhat bilobed, each lobe having 
several small protuberances, each of which terminates in a minute 
opening. 
Brethes (1902) reported only 2 pores per cocoon, an unusually low 
number for so large a cocoon, causing the species to occupy an anoma- 
lous position in the diagrammatic representation of cocoon size versus 
number of pores presented by Evans (1966, Fig. 209). Even 4-6 is 
a low figure for a cocoon of this size, but the fact that each pore has 
numerous small apertures may compensate for this. 
Structure of the Mature Larva 
There is no detailed published description of the larva of this 
