New York Agricultural Experiment Station. 515 



has observed them boring into the potato roots and rootstocks 

 in the same manner. 



At the time of the discovery of the grubs the soil around the 

 tubers was found to contain many white pupie (the resting form 

 of the grub). Some of the soil containing both grubs and pupae 

 was brought to the Station laboratory and turned over to Mr. 

 Sirrine, who put some of the tubers containing grubs into dirt 

 in a cage by themselves and some of the pupae into dirt in an- 

 other cage. The grubs, in fourteen days, and the pupa?, in eight 

 days, changed to the adult form, M^hich was in both cases the 

 small black flea-beetle Grepidodera (Epitrix) ciwumeris Harr. 

 This proved that the grubs found boring into the potatoes are 

 the same as the pupae found in connection with them, and that 

 both are the early stages of the common cucumber flea-beetle. 



These observations are important because they add considera- 

 bly to our knowledge of the habits and life history of the cucum- 

 ber flea-beetle, one of the most troublesome insects with which 

 Long Island farmers have to deal. 



There are several species of small jumping beetles, which are 

 known collectively as flea-beetles. The species which is the 

 most numerous and most destructive to potatoes, tomatoes, egg- 

 plants, etc., here, is a small beetle, about one-twelfth of an inch 

 in length, with the body black and the legs and antennae of a 

 dull yellow color. It is called the cucumber flea-beetle {Grepi- 

 dodera {Epitrix) cucumeris) because it was originally described as 

 feeding on the cucumber; but this name is inp^ppropriate, inas- 

 much as the insect feeds voraciously upon (juite a variety of plants 

 other than the cucumber. Although a common and injurious in- 

 sect of many years' standing, its Hie history is very imperfectly 

 known. Entomological writers have usually stated that the 

 grubs (larvae) are leaf-miners, feeding upon the interior of the 

 leaves infested by the adult beetles. Whether this is true we 

 cannot say. Mr. Sirrine doubts it. We are certain, however, 

 that the grubs feed on the tubers, roots and rootstocks of the 

 potato. They probably feed on the roots of other plants also, 

 but as yet we have no proof of this. 



