THE AMERICAN ENTOMOLOGIST. 



167 



case, however, it shows, under the micro- 

 scope, the longitudinal folds and creases 

 incident to the stretching, and compared 

 to the rectal ligament proper it seems to 

 lose importance as it is less needed; for 

 the succincti will generally attach when it 

 is severed or loosened from the retainers, 

 while in Apatura (at least as exemplified in 

 the North American species), which com- 

 bines the peculiarities of both the succincti 

 and suspensi* it does not become spe- 

 cialized, and the chrysalis seems to rely 

 almost entirely on the rectal ligament, as- 

 sisted by the partial holding of the delicate 

 larval skin, not only between what is left 

 of the sustainers and the ventral posterior 

 margin of the twelfth joint, but between 

 the ventral sutures of this last and the pre- 

 ceding joint. And here I would remark, 

 in conclusion, that the ventral borders of 

 two or three of the joints preceding the 

 subjoint are, in most chrysalides which I 

 have studied, so hardened that the mucous 

 membrane is actually grasped between them 

 and the deep sutures made in contracting, 

 or (what would be a more correct statement 

 of the fact) it remains, adhering in these 

 sutures after the outer skin is loosened, in 

 the same way that the membrane remains on 

 the sustainers. In some instances (espe- 

 cially in some species of Papilio) the pos- 

 terior border of the twelfth joint is pro- 

 duced into a medial transverse ridge fully 

 as prominent as that formed by the sus- 

 tainers, which l^ere are flattened and coa- 

 lesce. So that the sutures of some of the 

 terminal joints in the chrysalis do subserve 

 the purpose ascribed to them by Reaumur, 

 but in a somewhat different way. 



AN INTELLIGENT WASP. 



While it may not make any great differ- 

 ence in the final winding up of the affairs 

 of the human race whether we call the 

 intelligence of the lower animals instinct 

 or reason, still there can no great harm 



* The larva of Apatura attaches horizontally, making the 

 front pair of abdominal prolegs answer the purpose of the 

 girth ; but in the shedding of the skin this attachment is 

 severed, and the forming chrysalis assumes the perpendicular 

 position, and in the withdrawal and attachment of the cremas- 

 ter, it acts as the true suspensi. 



come from making observations, and be- 

 coming acquainted with the habits of the 

 minute as well as larger creatures with 

 which we are surrounded. The entomol- 

 ogist, in his investigations of the habits of 

 insects, frequently finds some species dis- 

 playing more than ordinary intelligence, or 

 exhibiting what would be called, among 

 the higher orders, reasoning powers, that 

 are frequently manifested in their evident 

 premeditated actions and calculations as 

 to the chances of accomplishing their pur- 

 pose by taking advantage of the variable 

 conditions or circumstances by which they 

 are surrounded. One of the most interest- 

 ing exhibitions of insect skill (if we give it 

 no better name) that has come under my 

 observation is annually performed by the 

 Handsome Digger Wasp {Stizus speciosus 

 Drury, Fig. 71,) that frequents my garden. 

 This wasp provisions its nest with the Dog- 

 day Cicada {Cicada canicularis Harris). 

 In my grounds it takes the Cicada prin- 

 cipally if not wholly, as I have never 

 found any other insect in its nest. This 

 wasp appears to know that it would not 



[Fig. 7: 



Stizus speciosus. 



be safe to dig its burrow in ground 

 that is being cultivated during the sum- 

 mer, and for this reason it frequents 

 paths and roads but little used, preferring 

 moderately light and dry soils. In such 

 places it digs its burrows, which are about 

 three-fourths of an inch in diameter and 

 two or more feet in length. They are not 

 perpendicular, but for the first twelve to 

 eighteen inches the wasp digs at an angle 

 of about forty-five degrees, then turns up- 

 ward a few inches to the end. 



The earth taken out of the excavation 



