1916] Williams — Life-History of Mefhoca stygia Say 123 



Adlerz made a few notes on the early stages and illustrates by 

 rather poor photographs, the Methoca larva and cocoon. The 

 latter ranged in length from 8 to 18 mm., being cylindrical, 

 brownish yellow, composed of many layers of silk, and provided 

 above with a sort of collar or neck. 



The Champions ('14, '15) have observed the habits of this 

 Methoca in England, where it inhabits the heathery and sandy 

 portions of the country. The prey is the larva of Cicindela cam- 

 'pestris and sylvatica. They observed Methoca go right down the 

 hole after her prey. The burrow is carefully filled. The wasps 

 worked well in captivity as with Adlerz. The egg stage is about 

 four days and the slender glassy larva matures in twenty days 

 from oviposition. The cocoon is dirt-free. 



Bridwell (1912) speaks of Methoca calif ornica as being "parasitic 

 in the burrows of tiger-beetles." Aside from this statement, I 

 know of nothing published on the habits of any of our few species. 



For three consecutive seasons (1913-1915) I have taken a few 

 females of Methoca stygia in two adjoining sandy areas in Needham, 

 a suburb of Boston, but not until the third season, when I took up- 

 wards of twenty specimens, did I attempt to secure any biological 

 data. The locality was but a few hundred feet in extent, and its 

 sandy and pebble-strewn soil, a favorite haunt for various fos- 

 sorial wasps, as Bemhex, Microhevibex, Bembidula, Tachytes, Tachy- 

 sphex, Cerceris, Oxybelus, Mutilla and others, was sparsely clothed 

 with small plants, conspicuous among which was a little sedge and 

 an inconspicuous Hypericum. A few small colonies of Cicindelid 

 larvae, probably C. punctidata Oliv. for the most part, undoubtedly 

 furnished the food-supply of the Methoca progeny. This wasp is 

 emphatically a lover of hot sunshine and was thus taken at rare 

 intervals running in zigzag fashion over the sand. But once did 

 I observe a Methoca attempt to enter a Cicindelid burrow and this 

 attempt was failure because of the very small size of the aperture. 

 Two Methocas confined in the field in glass tumblers inverted over 

 a burrow of a Cicindelid larva yielded no results, but other experi- 

 ments were in a degree successful. 



In the summer of 1915 Methoca was comparatively abundant 

 and twenty-six specimens were taken from August 1 to September 

 5, fifteen of these being captured on August 15. I confined sev- 

 eral in a quart preserve jar half filled with sand stocked with half 



