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The liabits of the different species in the family Sphecidae are varied ; 

 some preying upon spiders; others on cricliets, locusts, grasshoppers, 

 cockroaches, etc., while still others prey upon cut-worms or other lepi- 

 dopterous larvae. A large black digger-wasp belonging to the genus 

 Sphex was observed carrying off a specimen of the cotton locust, Ore lie 

 limnm gossypii. 



The blue digger-wasp (Chlorion coeruleum Dr.) is a common species in 

 all cotton fields and preys upon different species of crickets belonging to 

 the genus Gryllus. 



The blue mud-dauber {Ghalyhion, coeruleum Linn.) was also common. 

 I examined several nests built on the rafters of a cotton-gin shed and 

 found they were almost entirely filled with the large green spider, 

 Oxijopes viridans, so common on cotton. 



The common mud-dauber {Felopa'us cementariiis Dr.) was quite plen- 

 tifnl in the cotton fields, busily engaged in catching different spiders. 

 From one of its nests I obtained no less than thirteen distinct si)ecies 

 of spiders, although the most common of these was the Oxyopes viridans 



The Philadelphia digger-wasp {Isodontia pMladelphica St. Farg.), 

 although by no means common, was occasionally seen on cotton. It 

 preys upon the cricket, (Ecanthus fasciatus Fitch. 



Ammophila pictipennis Walsh, A. vulgaris Or., and A. gryphus Smith 

 were also frequently met with in cotton fields, and I feel satisfied all 

 prey on different lepidopterous larvte found on the cotton. 



In the family Pompilidte four sjiecies were common, viz., PompUus 

 pltUadelpMca St. Farg., P. americanus Beauv., P. tropicus Linn., and 

 r. (vtliiope Cr. All are predaceous on spiders. 



The services performed by the species belonging to the family of 

 paper-making wasps, or Vespidte, to the farmer, fruitgrower, and 

 planter have never been thoroughly appreciated, and I am astonished 

 to find so little in our literature concerning them. In many cases the 

 services performed by these wasps are much more valuable than those 

 of the true parasitic Hymenoptera, the ichneumon -flies, chalcis-flies, 

 etc., and almost any one with a little observation of his own can readily 

 substantiate this fact. The food of the young wasps is composed 

 almost entirely of chewed- up caterpillars and other destructive insects, 

 and supplied to them by either the worker or female wasp. 



The following species were observed in the cotton fields : 



The large-ringed wasj) {PoUstes annularis Linn.). This is one of the 

 largest species in oar fauna, and is common in the whole cotton belt. 

 On August 14 I saw one of these large wasps seize a small-sized cotton 

 worm, fly off with it to a neighboring bush, and then deliberately chew 

 it up into small fragments, after which it flew away to its nest. 



The Canadian wasp {PoUstes canadensis Linn.). A smaller species 

 than the preceding, but bearing a slight resemblance to it, was also 

 observed chewing up a caterpillar, but the name of the caterpillar was 

 not ascertained. 



