REPORT OF THE ENTOMOLOGIST. 205 



never found the larvae feeding upon the vines, I have taken the ima- 

 goes flying about them as well as the morning glories spoken of above. 



This flv is described as "a small four-winged creature, about the size 

 of a common house fly, or a little smaller. It is black, and the wings 

 are dusky. The female abdomen is yellowish brown." It is shown 

 in the accompanying illustration (Fig. 16) in egg, larva and imago 

 stages. 



Sweet potato beetles differ somewhat from the insects that attack the 

 ordinary potato, in their structure. A reference to Figs. 18, 20, 21, 

 and 22, will give the reader an idea of the appearance of these insects 

 which are popularly called tortoise beetles — a very good name indeed, 

 since their shape and general movements remind one very forcibly of 

 that animal. 



Here in Nebraska we are more or less frequently reminded of the 

 fact that these tortoise beetles are quite partial to the sweet potato vines 

 as a food plant. There are at least four or five distinct species of these 

 beetles concerned in these attacks here in the state. 



The tortoise beetles have been admirably described in vol. I of the 

 American Entomologist, by Prof. C. V. Riley and B. D. Walsh, and 

 I cannot do better than to quote from that article in treating of them 

 here. These gentlemen write of the beetles as follows : 



"The insects which attack the sweet potato plant are few in species 

 and belong almost entirely to that group of beetles popularly known 

 as tortoise beetles. With the exception of the Cucumber Flea beetle 

 (Orepidodera cucumeris), and a few solitary caterpillars, we have 

 never found any other insect on this plant ; but we regret to say that 

 these tortoise beetles are of themselves sufficiently numerous in indi- 

 viduals and species to often entirely destroy whole fields of this escu- 

 lent, and they are especially severe on the plants when newly 

 transferred from the hot-bed. 



"These insects are at present included in the great family Chryso- 

 melidse [the family of leaf beetles, which includes the Colorado potato 

 beetle, Striped Cottonwood beetle, flea beetles, etc.], though they were 

 formerly placed in a separate family (Cassididse) by themselves, and 

 there certainly are few groups more strongly characterized. They are 

 almost all of a broad subdepressed form, either oval or orbicular, 

 with the thorax and wing-covers so thoroughly dilated at the sides 

 into a broad and flat margin as to forcibly recall the appearance of a 



