39 



the latter part of August, possibly to place eggs for 

 another brood. 



3. The remaining moth {Lithocolletis qstensackenella) 

 produces a yellow blotch-mine placed anywhere on the 

 upper side of the leaflets, and at first narrow and tortu- 

 ous, but finally enlarging suddenly and becoming more 

 or less circular in outline. The mines begin to appear 

 early in June (Observed by me first, June 11), are empty 

 by the first of August, the moths having matured, and a 

 second lot begins to become noticeable about August 24. 



4. The fourth and last miner is, when adult, a small 

 beetle {Odontota scuteiiaWs), with somewhat flattened body 

 measuring nearly .25 inch in length. It is black with 

 the exception of the thorax and the sides of the wing- 

 covers, these being tawny yellow. It is very injurious to 

 black locust, and appears to attack apple leaves at times 

 also. Mr. John W. Buck, of Midway, wrote me some- 

 time ago enclosing specimens of the beetle and stating 

 that it was ruining the leaves of his apple trees. The 

 adults become common on the leaves of locust trees about 

 May 22, and the peculiar egg-masses can be found by June 

 1. The-masses consist of five or six discoid eggs placed one 

 behind another, with their flattened surfaces in contact. 

 The young grubs, which are not very diff'erent from those 

 of the moths, cut through the side of the eggs next the 

 leaf and bore down into the substance of the latter, all of 

 those from an egg-mass living for a tioae in a single mine, 

 but later scattering and making each a mine of its own. 

 When removed from their mines they cut a slit in the 

 leaf with their jaws and work their way into the leaf 

 again very rapidly, the whole length of the body being 

 concealed in less than an hour. By June 30 the grubs 

 begin to change to pupse, some leaving the mines for this 

 purpose, and shortly afterward the beetles appear. 



