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THE LUNA AND POLYPHEMUS MOTHS. 



The two silk-worm moths which we low. The wing expanse ranges from 

 figure this month both possess a point of three and three-fourths to five and one- 

 excellence far in advance of any other of half inches. 



our native silk-worm moths ; Luna on ac- During April or May the mother moth 



count of its graceful form and delicate lays her dark-brown or chocolate-colored 



colors, and Polyphemus for the silk of eggs upon hickory, walnut, beech, oak, 



its cocoons. and a few others of our forest trees. The 



It seems that most persons who speak limited number of food plants is doubt- 

 of the Luna moth (Tropaea luna) feel less one reason for the rarity of the 

 called upon to give a more or less poetic moths, as compared with such a corn- 

 description of it. This, I hope, has been mon and almost omnivorous larva as Ce- 

 rendered unnecessary by the colored cropia. A single moth may lay about 

 plate, so that it will suffice simply to men- one hundred eggs, which are smaller than 

 tion that the beautiful shade of green is those of Polyphemus. These hatch in 

 of very rare occurrence among our larger about ten or fifteen days, the larva mak- 

 moths, and that no other has the long, ing its escape by eating a circular hole in 

 graceful "tails" on the hind wings, a the shell. Occasionally a young larva 

 .characteristic which adds greatly to the may be seen crawling about for a short 

 beauty of this insect. time, carrying upon its head or tail the 



This moth does not seem to be very empty shell. 



abundant anywhere, but when once seen The adult larva is about three inches 

 will long be remembered on account of long, of a delicate pale green, a color very 

 its great beauty. The green and yellow difficult to preserve in the dead larva, 

 colors are evidently very closely related, Those on the plate have lost this delicate 

 because either one may, to a greater or green and have become yellow, but show 

 less degree, replace the other, so that the form perfectly. This larva is very 

 some of the moths have quite a strong, much like that of Polyphemus, but may 

 yellowish tinge. One of our common be distinguished from it by possessing a 

 swallow-tail butterflies (Iphiclides ajax) longitudinal pale yellow lateral line, 

 possesses a very similar green color in its which is not found in Polyphemus. Since 

 wings, but does not seem to show this the cocoon is quite thin and contains but 

 tendency to replace the green by yellow, little silk, it is considered of but little 

 On the wings are four eyespots which are value. This cocoon is spun among two or 

 also found in Polyphemus. These are three weaves, and is about two inches 

 remarkable in that they are transparent long. Some authors claim that the cocoon 

 in the center. This clear area in Luna is falls to the ground with the autumnal fall- 

 quite small, while in Polyphemus it is ing of the leaves; others that it trans forms 

 about as large as the entire eye spot of on the ground among the fallen leaves. 

 Luna. The legs are brown and colored The cocoon is quite similar to that of 

 like the front edge of the fore wings. The Polyphemus, but not so firmly attached 

 hairs on the body and at the base of the when fixed to a stem. The moths emerge 

 wing are very long and are white or yel- in April and May, there being only a 



