268 OHIO EXPERIMENT STATION: BULLETIN 332 



chestnut, elms, poplars, willows, birches, witch hazel, linden, hazel- 

 nut and others. In the vicinity of Wooster it is more commonly- 

 found on maple and oak than other hosts. 



Distribution. — This insect ranges across the entire continent 

 and into Mexico on the south, according to Holland. 



Natural enemies. — Riley (34) states that the following insects 

 are parasitic on the polyphemus moth : Ophion macrurum Linn, 

 Chalcis mariae Riley and Tachina sp. 



Control. — Control measures rarely are necessary except in the 

 case of newly-set, valuable trees, when hand picking is practicable 

 and effective. 



THE LUNA MOTH 

 {Tropea luna Linn) 



Description. — The most gorgeous moth in Ohio is the luna 

 moth. It measures more than 4 inches across its expanded wings, 

 and on the back wings are two long swallowtail appendages. The 

 color is a delicate pale green, the fore wings being margined on the 

 front with a strong band of lavender. On both the fore and the 

 hind wings are prominently marked spots, those on the fore wings 

 appearing somewhat like half-moons and those on the hind wings 

 somewhat like full moons. It is because of this resemblance that 

 the insect is given its name. The larva is about 3 inches long, stout 

 in build and pale green in color. Adorning the body are six rows of 

 small pink tubercles, each with one or more black hairs springing 

 from it. (See Plate XLII, Fig. 2.) 



The cocoon is spun among the leaves, is thin and papery. It 

 does iiot adhere permanently to the tree but falls to the ground in 

 autumn. 



Life history and habits. — The seasonal development is quite 

 like that of the preceding species. 



Nature of work. — The larvae are leaf feeders but never abun- 

 dant. 



Food plants. — Doctor Felt records the species feeding on wal- 

 nut, oak, hickory, chestnut, butternut, sweet gum, birch, willow, 

 beech, plum and ironwood. Doctor Holland (33) states it is quite 

 fond of persimmon. 



Distribution. — Doctor Holland gives the range of this species 

 "from Canada to Florida and westward to Texas and the trans- 

 Mississippi states as far as the region of the Great Plains." 



THE PEOMETHIA MOTH 



(Callosamia proriiethia Drury) 



Description. — The promethia moth also is one of the large 

 caterpillars of the silkworm group and is much more abundant than 



