6g PROCEEDINGS OF THE NATIONAL MUSEUM vol. 82 : art. 28 



near the tip, and another marginal, less dilated fillet, confluent with 

 the sutural vitta at tip; region of the origin of the posterior feet 

 black ; thighs rufous ; tarsi, and a line on the superior edge of the 2 

 anterior pairs of thighs together with a line on the inferior edge 

 of the tibiae, black. Length more tlian three tenths of an inch. 



" The arrangement of the lines of the elytra are similar to those of 

 A. caroliniana Fabr. The head is sometimes black at base and the 

 two intermediate thoracic spots are confluent. Found in consider- 

 able numbers on common elder {Samhucus) and some other shrubs. 

 On the evening of the IGth of June, I observed great numbers of 

 these flying in a southeast direction from near St. Louis, obliquely 

 across the Mississippi towards an island, the wind at the same time 

 blowing moderately from the eastward ; the subsequent evening, about 

 the same hour, they returned by the same route reversed, the wind 

 directly opposing them ; both of these days were very warm. During 

 our progress up the Missouri River, I observed several times similar 

 migrations of this species." 



I have been unable to learn of any species of Disonycha that feeds 

 on elder. In view of the fact that elder frequently grows in the same 

 locality with willow and the fact that these insects were exceedingly 

 abundant, Say may have seen specimens on elder although the willow 

 was the real food plant. This is indicated in his statement that they 

 occurred on " some other shrubs." His description unfortunately 

 applies equally well to three species of Disonycha, all of which occur 

 in the locality given — alternata, pluriligata, and functigera. For 

 further discussion, see remarks under those species. 



U.S. GOVERNMENT PRINTING OFFICE: 1933 



