236 On two Species of the Sphex or JVasp, 



e( The whitlow of the third species is very difficult to 

 cure : the horn must be cut, and the flesh taken off also ; 

 and the carious bone must be then scraped, and seared with 

 a, red-hot iron." 



The manner of operating with the knife, in order to 

 discover the seat of the disease, is extremely well described 

 in the above memoir. The analogy between the treatment 

 of the whitlow in human creatures and that in animals, 

 shows how efficacious the immersion in hot water is as re- 

 commended by the author; and the careful cleaning of the 

 ulcers, upon which he insists, is extremely important. I 

 entreat that some intelligent agriculturists may communi- 

 cate to the public their observations from time to time on 

 this disease, and the best methods of cure. 



XXXVI. On tuo Species of the Sphex or IVasp, found in 

 Virginia and Pennsylvania, and probably existing through 

 all the United States. By H. Latrobe, Esq. 



J. he two species of sphex whose astonishing industry pre- 

 sents such interesting particulars, are known in America by 

 the names of the Hue wasp, the mason and the dirt-dauber. 

 These wasps are distinguished among all the remarkable in- 

 sects which belong to the order of the hymenopterce of Lin- 

 naeus, by the singular and cruel manner in which they pro- 

 vide for their young. 



The two species of sphex now mentioned are distinguished 

 from each other by their manner of building, and by the 

 form of their bodies; but they are quite similar in their 

 manners, in the materials they employ in making their cells, 

 and in tjhe food they prepare for their progeny. 



The first is probably the sphex ccerulea alis fnscis of Lin- 

 naeus*. It is by far the most common: its *feelers are 

 sharp-pointed, and are extended when the insect is at work; 

 on its snout it carries a strong beak, with which it works 

 iidevvays, by making furrows on the surface of its little 



• The blue ichneumon wasp, with gilt wings. (De Geer.) 



cells, 



