230 



THE AMERICAN ENTOMOLOGIST. 



\ 



THE BOTAl HORMlD-CATERPnJiAK. 



{Geraiocampa [Cithronia]regalis, Fabr.'i 



This iiitiect. which is the subject of our color- 

 ed plate, and which is there illustrated in its 

 three ditl'erent stages of larva (a), chrysalis (6) 

 and noth (c), is one of the largest and most 

 beauii 'ul of its order, and its splendor is scarcely 

 equaled by any other North American species. 

 It was oviginally described in 1793 by Fabricius, 

 under t ic name of Bombyx regalis, and was 

 afterwa lis placed in a new genus (Citheronia) 

 ei'ected by Hiibner. Dr. Harris,* who made it 

 the type of a family (CERATOCAMP.ujyE), and 

 who describes and figures it under the name of 

 Ceratoriuiij)a regalis, called it in popular lan- 

 guage the ''Regal Walnut Moth;" but as it is 

 found ii; well nigh equal abundance on the 

 I'.ia'-l ^V'alnut, Butternut, and Persimmon, and 

 mes on the Hickories and Sumachs, and 

 . much oftener seen in the caterpillar than 

 .ae moth state, we prefer that it shall be 



• lularly known by the above translation of its 

 ientitic name. 



Harris's engraving of the caterpillar scarcely 

 •'ves a just conception of it, and was evidently 

 iken from an alcoholic specimen. Our figure 

 •as taken from a living specimen whicli was 



ji id feeding on the leaves of the Persimmon 

 ' Union County, in South Illinois, and it mea- 

 ired over five inches when crawling. Full 

 ;-own specimens were also sent to us last year 

 om Bushberg, Mo., and from Brighton, Ills., 

 id we found one in the neighborhood of St. 

 <»uis,JHo ; but the insect is quite scarce even 

 •s far south as the above mentioned points, and 

 'cours still more rarely farther North. 



It is single-brooded, and sometimes remains 



the ground, in the chrysalis state, fully eleven 



• mths of the year. The moths, in the latitude 

 St. Louis, usually issue during the last half 

 June, and the caterpillars are found full- 



;own from the middle of August to tlie middle 

 September. We have never seen the joung 

 terpillars, but in 1828, Dr. Harris found three 

 the eggs of this fine insect on the Black Wal- 

 .it, speakhtg of which he says: "They were 

 -st hatched at the time and the caterpillars 

 ere near to them resting on a leaf. The posi- 

 on of these young insects was so peculiar as 

 I attract att(iution, independently of the long 

 i-anching spines with which the fore part of 

 loir body was armed. They were not stretched 

 ut in a straight line, neither were they hunched 

 1> like the caterpillars of tlie Luna and Poly- 



•Iiir bisects, 1,,,. 3W-9, 



phemus moths ; but, when at rest, they bent the 

 fore part of the body sideways, so that the head 

 nearly touched the middle of the side, and their 

 long horn-like spines were stretched forward, 

 in a slanting direction, over the head. When 

 disturbed, they raised their heads and horns, 

 and shook thera from side to side in a menacing 

 manner. These little caterpillars were nearly 

 black ; on each of the rings, except the last 

 two, there were six straight yellow thorns or 

 spines, which were furnished on all sides with 

 little sharp points like short branches. Of these 

 branched spines, two on the top of the first 

 ring, and four on the second and the third rings, 

 or ten in sill, were very much longer than the 

 rest, and were tipped with little knobs, ending 

 in two points; they were also movable, the 

 insect h.aving the power of dropping them al- 

 most horizontally over the head, and of raising 

 them up again perpendicularly. On the ele- 

 venth ring there were seven spines, the middle 

 one being long and knobbed like those on the 

 fore part of the body ; on the last ring there 

 were eleven short and branched spines. After 

 casting its skin two or three times, the cater- 

 pillar becomes lighter-colored, and gradually 

 changes to green ; the knobs on tl e long spines 

 disappear, their little points or branches do not 

 increase in size, and finally these spines l)ecome 

 cui-ved, turning backwards at their points, and 

 resemble horns." 



The full grown caterpillar,* with its immense 

 green body and its horn-like spines looks truly 

 formidable, while a peculiar habit which it has of 

 spitefully wriggling from side to side, very un- 



*As no comprehensive description of either the larva or 

 chrysalis has been published, and as the horns of the larva 

 are not quite correctly represented in our flgiu-e, we annex 

 the following descriptions which were drawn up from three 

 living specimens. 



Description of full grown larva. — Average length when at 

 rest, 4.90; diameter, 0.60 inch. General color, green with a 

 yellow c;ist. Smooth and pcjlished. Thoracic segments 



; I !>-. -1 "|- ;ill, with 



> h ' II ^. r l.huk |.;iti'hes in 



inn 111 _' 4, ."). H, 7, 8, i) and 



M nil M.\ .short black back- 

 irati-il spines, which spring 

 Uil-blui- gi-ound, which in 

 iilui- tiMnsverse ridge: H, 

 twr.ilnrsal ones being sup- 

 mi 1;iiki.'i-: 12, with seven 

 ■li a lateral posteriorly and 

 .nil hand, which is abrupt 

 li siiii.kv-lilack, but which 

 rn iiii.inh.ilv- .stigmata 

 Mk\ liiir riiiiiini;;' from each 

 ■M -mall, Mllin\isli-brown 



-11, ii- liriwr.ri ilif larger 

 anal iirol,--s niil wardly, of 

 IS laiL,'!- hiiins; the caudal 

 LCh side, and the anals each 



Thoracic It-gs also of the 



merges gradually into thi- -i- 

 large, oval and black, with a -n 

 to me lower horn Cerviial -hi 

 and with two cuneiform hla.l 

 horns. Head, caudal pluti- ami 

 the same orange-brown color 

 plate with a minute black wai-t e 

 with one at their lower edge. 



