no 
Psyche 
[March 
melting of the snow, the young stages were washed to the ground, 
thereafter burrowing into the soil. Following that, they would forage 
as saprophiles, since Withycombe (1922) has found that larvae can 
feed on leaf mold. Promising moss-covered boulders, standing on a 
loose, fine and sandy soil, were therefore trenched on the run-off side 
to a depth off a foot or more, and the soil carefully sifted through 
Tyler screens down to 16 meshes to the inch (0.99 mm openings). 
This seemed a hopeful attack at the time because Strubing (1950) 
had found that B. hyemalis, during periods of drought, descend to a 
depth of as much as 20 cm below their mosses, which grow on soil, 
to reach a suitably humid surrounding. No Boreus were found. 
During one collecting period in mid-August there was a brief but 
heavy shower which, within 20 minutes, brought the mosses on the 
boulders to a fresh, expanded green state, and soaked their sods 
through. When the damp sods were broken or sliced open, there 
amid the rhizoids were the larvae and pupae within small ellipsoidal 
and cylindrical spaces that had readily cleaved open ! During dry 
periods these cells, which are only slightly larger than the stages 
enclosed, harden and act thereafter as a coherent whole, appearing 
as no more than larger, compact particles of the sandy soil and 
organic debris of the desiccated sod. When such sods are broken and 
crumbled, these cells remain intact, even under the stresses of sifting. 
Their inner walls are very smooth, and are perhaps cemented by 
salivary secretions, but not by silken threads as has been suspected 
or claimed for the pupal chambers of B. westwoodi (Brauer 1863) 
and B. hyemalis (Withycombe 1922, Syms 1934). It is possible that 
salivary secretions also make their walls impervious to water loss. 
Thereafter search became routine during the predominantly dry 
periods for the desiccated mosses on their boulders need only to be 
soaked with water. 
It is clear that B. notoperates is well adapted by its earthen cham- 
ber for survival during periods of drought. T he larva must do most 
of its foraging during the spring before the moss turfs become dry, 
and thereafter as infrequent opportunity permits following scattered 
storms on the mountain. 
Associated Mosses 
Records of the mosses with which Boreus is associated in one way 
or another have been made 'for only seven or eight of the twenty- 
seven or so species of Boreus known (species list in Svensson I97 2 )> 
