292 



The larva, which is described from the living specimens, is one of 

 the most beautiful natural objects known to me. It is about 1.80 inch 

 long and .45 inch in diameter, of a bright grass-*reen color, with 

 scattered whitish tubercles, or short, robust thorns, very thickly set 

 towards the anus, and a regular row of them at the anterior dorsal 

 edge of the three or four first segments. Laterally, immediately be- 

 neath the line of spiracles, which are normal, from the third thoracic 

 to the penultimate abdominal segment inclusive, there is a narrow, 

 whitish vitta, bordered above by purple. On each side of the dorsum of 

 thoracic segments 2 and 3 are two slender transversely arranged re- 

 curved horns, one-fourth inch long, tubercled, and either bluish or 

 purplish at tip. On each side of joints 5, 7 and 9, or occasionally only 

 on 7 and 9, and in three specimens on 5, 7, 9 and 10, are a pair of 

 slightly recurved, highly-polished, silvery or nacreous thorns, the 

 outer one short and robust, the inner one slenderish and .15 inch long. 

 In one of the three specimens having a lateral pair of nacreous thorns 

 both on 5, 7, 9 and 10, there are, in addition, single rudimental nacre- 

 ous thorns on 6 and 8, in range with the longer nacreous thorns on 5, 

 7, 9 and 10 ; and in another one of the three there are such rudimental 

 thorns both on 4, 6 and 8. In still another specimen, which has the 

 normal pair of thorns on 5, 7 and 9, there is only a single lateral 

 thorn on 10. On the dorsum of 11 is a horn similar to those on 2 

 and 3. Anus horizontal. Body, beneath, green, with smaller and 

 denser tubercles. Legs rufous, tipped with brown-black ; prolegs 

 brown-black beneath as well as their hooks. Head rufous, rugose, 

 with a longitudinal stria divaricating at an angle of 45° two-thirds of 

 the way to the mouth, which is obfuscated. In two out of three alco- 

 holic specimens, there is, on the middle of segments 2-11 or 4-10, just 

 below the lateral white vitta, a short, robust black thorn, which I did 

 not notice in the living insect, and several of the ventral tubercles 

 are also brown-black. Described from twelve to twenty specimens. 

 Food-plant, honey-locust. The first larva met with, which was full- 

 grown and shortly after went under ground, occurred July 10. Most 

 of my larvEB buried themselves three or four inches in the earth, but 

 one of them only buried one-half of its body under the earth, the re- 

 maining part being covered by some dry leaves. 



The i^upa, which is not contained in any cocoon, is of the usual 

 dark chestnut color, with deep, coarse punctures towards the anus, 

 and has its anterior end ai-med with fifteen to twenty short, robust, 

 hooked thorns, pointing in various directions. The piece covering 

 the antennas distinctly exhibits their bipectinations. The pronotum 

 is obseniicircular, placed immediately behind the origin of the anten. 

 nee, and bears on its hinder suture, near the lateral apex of the semi- 

 circle a spiracle, in the form of a semi-circular opening .02 inch long. 



