THE STATE ENTOMOLOGIST. 123 



The cocoons are found upon the Ash, Sassafras, Wild cherry, Tulip 

 tree (Lirlodendron,)HwGbtgiim (Liquidambar), Spice bush (Zm^/era), Maple 

 Plum, Poplar, Azalea, Cephalanthus, Snowdrop tree (Halesia), Barberry, 

 Birch, Bayberry {Myrlcd) and Lilac. Of course it does not follow that the 

 worm feeds upon all trees and shrubs Ujjon which its cocoon is found : 

 •on the contrary, there is good evidence that it often prefers to wander onto 

 some tree, other than that on which it fed, when about to spin up ; and Dr. 

 Fitch (Pep. HI, § 80) has shown that in New York it spins up by preference 

 on Lilac. But I have fed it successfully on the live trees first mentioned 

 while my correspondents in Pennsylvania and Marj' land have fed it on Tulip 

 tree, Sweet gtim and Spice bush ; and there is reason to believe that it will 

 feed upon the others. In flict Mr. Chas. S. Minot of Boston, Mass.^ informs 

 me that at a j^inch it will feed on Arbor-vitfe. It is most commonly found 

 on Sassafras and Cherry with us, while singidarly enough. Dr. Fitch has 

 shown that in his localit}', it prefers the Ash, and does not touch Sassafras 

 even when adjoining Ash. These facts go to show how a si^ecies maj^ get 

 to prefer different trees in different sections of a country, and indicate how 

 incipient races at first, and in time varieties and species may be formed. 



NATURAL ENEMIES. 



The cocoons are often gutted b}- birds, hard pushed for food in the 

 winter; while the worm is attacked by several parasites. The cocoon is of- 

 ten found to contain numerous other small silken cocoons, ver}" much as rep- 

 resented in Figure 40, but formed of a somewhat darker material ; and from 

 the^s I have brei Oryptus nunoius, Say which differs principall}^ from ex- 

 frematis, Cresson, in having the ovipositor shorter than the abdomen as in 

 Figure 41, b ; instead of nearly twice as long as at a*. Ghalcis marioe also 

 preys upon it, and Mrs. Chas. S. Minot has bred an Ichneumon, an Ophion 

 and a Tachina-^y from it. 



THE LUNA SILKVYOEM— ^^tocMS lActias'] Luna^ljinn. 



(Leijicloptera , Borabycicl;e . ) 



Whichever of the preceding moths may carry off the palm of beauty in 

 the eyes of different persons, no one will hesitate for a moment to accord 

 to Luna, our " queen of the night," entire supremacy in grace, elegance and 

 chasteness. No other N. A. insect can win this distinction from her. All 

 the large moths figured in this article on silkworms draw forth expressions 

 of admiration from those who see them in my cabinet ; but the delicate green, 

 relieved by the ej^e-spots and hy the broad purple-brown or lilaceous an- 

 terior border; the soft downy hair of the body, and above all the graceful 



varieties of P/viflf/ft. a. From the fact ih it this ex leptional form his been reared from cocoons spun 

 up arouufl the base of tre_'s, I infer tnat it i; often produced from enfeebled .worm^ which hiive fallen 

 to the ground. 



•For further details ; ee i aje 111. 



