INSECTS AFFECTING PARK AND WOODLAND TREES 325 



Locust leaf miner 



Odoiitota dorsalis Thunb. 



Blisterlike spots or eroded skeletonized areas on honey locust leaves, may be due to 

 the work of the larvae and adults of this insect. 



Dr Fitch describes the work of this leaf miner in his 5th report, 

 briefly characterizes the larva, and states that he has never met with it in 

 the eastern section of New York. This insect was also brought to the 

 attention of Dr Lintner at various times, though he never found it in his 

 extensive collections in Albany and Schoharie counties. It is very abun- 

 dant, however, on Long Island and has been met with by the writer in 

 Chautauqua county, where its work was very common in and about West- 

 field Aug. 15, igo2. 



Injuries. This insect is occasionally so abundant that a large propor- 

 tion of the foliage on the honey locust is ruined. The larvae form large 

 blisterlike spots under the lower epidermis. The adult beetles feed on 

 the under surface of the leaves, eating away the more delicate portion 

 between the larger veins [pi. 45, fig. 2]. Dr H. G. Dyar, writing to Dr 

 Lintner Aug. 31, 1896, stated that this insect was so abundant at Yaphank 

 L. I., as to injure the trees very seriously, and cause a considerable propor- 

 tion of the foliage to drop. Mr Chittenden records an instance where this 

 species was exceedingly destructive in Fairfax coimt)', W. \'a.. where all the 

 locust trees over an area of several square miles were apparently dead, 

 looking as though a fire had swept over the country. On one tract of 300 

 acres, on which were many locusts, not a tree could be found, either young 

 or old, that was not in bad condition. 



Description. The adult beetle is about J^' inch long, with the head, 

 appendages and under surface and a median triangular area, widening 

 posteriorly on the wing covers, coal-black, the remainder of the wings and 

 the dorsum of the thorax are an orange red. The thorax is irregularly and 

 deeply punctured and the wing covers strongly ridged and ornamented with 

 deep, nearly confluent, thickly set rows of punctures. 



