236 ENTOMOLOGICAL SOCIETY 



riously throughout the Mesilla valley in New Mexico.* Mr. 

 Townsend has failed to rear the adults, but has collected these 

 saw-flies on the cottonwoods just as the leaves were beginning to 

 expand, early in April. He also reports that they were very 

 abundant, flying everywhere during the latter part of March. A 

 saw-fly belonging to a different genus, however, mines the poplar 

 leaves in the larval state in exactly the manner described by Mr. 

 Townsend ; and the reference of the New Mexican species to 

 the poplar-leaf miner is therefore still open to question. 



So far as known, the larvae of the European species feed ex 

 posed on the surface of leaves of Betula and Tilia. 



Mr. Coquillett read the following : 



ON THE NESTING HABITS OF THE DIGGER-WASP, BEMBEX 

 CINEREA HANDLIRSCH. 



By D. W. COQUILI.ETT. 



On September n, 1891, in company with an enthusiastic nat 

 uralist, Dr. A. Davidson, of Los Angeles, California, the writer 

 spent several hours in digging out the nests of this wasp in a sand 

 bank near the ocean beach adjoining the little village of Redondo, 

 a summer resort distant about ten miles from Los Angeles. The 

 sand-bank in question is in the form of high ridges with intervening 

 depressions, and the nests were located in or near the bottom of 

 these depressions. The mouth of the burrow leading to the nest 

 was closed, and the only indication of its presence was a more or 

 less circular pile of loose sand surrounding it. The burrow ex 

 tended obliquely -downward a distance of from sixteen to twenty 

 inches, passing entirely through the loose surface sand and en 

 tering the moist, hard-packed sand beneath. At a point about 

 four inches before its terminus a branch was formed which 

 passed beneath the main burrow, going still deeper into the earth. 

 The entire burrow had somewhat the form of an obliquely in 

 verted Y, one arm of which lay directly beneath the other. 

 Nothing was found in the main burrow, the nest being invari 

 ably located at the farthest end of the branch. 



A large number of the burrows were examined, and all of them 

 were constructed on this same plan, the philosophy of which is 

 not very apparent. It cannot be for the purpose of excluding 



* Canadian Entomologist, vol. xxv, p. 304, December, 1893. Zoe, vol. 

 iii, pp. 234-236, October 1892. 



