192 Maine Agricultural Experiment Station. 1918. 



leaves is shown in figure 94 of Bulletin 195 of this Experiment 

 Station. 



Mating. As is usual with chrysomelid beetles, each female 

 pairs several times during the season, before she has finished 

 depositing all of her eggs. 



Number of eggs deposited by one female. These beetles 

 do not thrive in confinement as well as most flea-beetles do, and 

 the number of eggs deposited under laboratory conditions is 

 probably somewhat smaller than the number normally deposited 

 under natural conditions. The greatest number of eggs that was 

 deposited by any one female was 181 between June 11 and July 

 15 (1917). The greatest number laid by one beetle in 24 hours 

 w r as 17. 



Food Plants. 



Natural food plants. The only plant on which the writer 

 has ever found this species in the field is the white elm, Ulmus 

 americana L. But in the laboratory, the larvae, especially, ate 

 with more or less readiness a surprisingly large number of other 

 plants. 



FOOD-PLANTS OF THE ADULT ELM FLEA-BEETLE.* 



(i) Eaten readily. 



White elm, red elm, basswood. 



(ii) Eaten indifferently. 



Cultivated willow, heart-leaved willow, petiolate willow, 

 beaked willow, wild strawberry, cultivated strawberry, 

 wild rose, cultivated rose, Japanese rose, fireweed, low 

 blueberry. 



(iii) Refused. 



Aspen poplar, balsam poplar, sweet fern, hazel, gray birch, 

 alder, red oak, syringa, smooth gooseberry, European 

 gooseberry, cultivated spiraea, apple, mountain ash, choke 

 cherry, red cherry, wild plum, cultivated plum, sugar 

 maple, woodbine, marsh fireweed, evening primrose, red 

 osier dogwood, bunchberry, sheep laurel, lilac, Joe Pye 

 weed, grape ( !). 



*For the scientific names of the plants used in these tests, see page 

 171. 



