18 PAPEES OX INSECTS AFFECTING VEGETABLES. 



This species was observed in 1908, by Mr. D. K. McMillan, at 

 Brownsville, Tex., working in colonies on the foliage of pigweed 

 {Amaranthus retroflexus), and on spiny amaranth (A. spinosus), the 

 larvae webbing and folding the foliage in the previously described 

 manner. The colonies in question came under observation on April 

 30, May 14, June 15, and November 5, 1908. Mr. McMillan also 

 observed the larvae in large numbers during the spring of that year, 

 working on " spinach" in the Rio Grande Valley and on beet foliage 

 at Brownsville. 



On May 28, 1909, Messrs. McMillan and H. O. Marsh observed these 

 larvae at Brownsville, Tex., embedded in the leaves of Amaranihus 

 retroflexus. The larva? were not in abundance at that time, doubtless 

 owing to the extensive parasitism in May and June of the preceding 

 year (190S). This was the first observed appearance of the insect 

 that year. 



During the same year this species twice came under the observa- 

 tion of Mr. H. M. Russell, in the first instance at Boynton, Fla., on 

 January 27, 1909, when the larvae were found hi great abundance on 

 the foliage of table beets. They had nearly stripped an early plant- 

 ing and were also abundant on a later planting. In many cases the 

 larvae were present on the underside of the leaves and had drawn the 

 leaf into a fold, inside of which they were concealed. In other a 

 the larvae were concealed by the folding up of the leaf from the edge, 

 while in further instances two beet leaves were fastened together in 

 such a manner that the larvae were concealed between them. In 

 feeding, the leaf substance is usually entirely eaten through to the 

 surface, the leaf skeleton alone being left. The larvae void a very 

 soft excrement which produces a filthy condition of the leaves. 

 Later on, March 3, the larvae were found by Mr. Russell in fair abund- 

 ance on beet tops at Cutler, Fla., and still later at Miami, Fla., on 

 rrantlius retroflexus. 



Beginning with March, 1909, parasitic cocoons were seen on the 

 leaves of beets, and early parasitism was indicated by the presence 

 of parasitic cocoons on other food plants. Amaranth is abundant 

 along the edges of many fields in southern Florida, and it is impossible 

 to destroy it to a very great extent, as it grows luxuriantly on hun- 

 dreds of acres of unclaimed lands. It costs from $15 to $75 an 

 • to clear hammock for planting. Perhaps, therefore, it is just as 

 well to allow the amaranth to remain and to spray the weeds as a 

 means of keeping this pest in check. There is little doubt that un 

 the parasites continue their good work the species is likely to cause a 

 serious outbreak at almost any time hi the future. 



Of one lot of material received at "Washington, D. C, the larvae 

 of which were nearly mature, it was noticed that they began to -spin 

 up" preparatory to pupation on May 7; the following da}' some of 



