TIGER-LiiETLES VS. COTTON- WORMS. 173 



ton fields in the vicinity of Selma, Ala., occasionally darting to the 

 ground and seizing some insect. With some difficulty a specimen was 

 captured while engaged in sucking the juices of a young grasshopper 

 (Caloptenus sp.) During the past summer Mr. Trelease forwarded sev- 

 eral of these insects to the department from Minter, Dallas County, 

 Alabama. He stated that they \\ ere vt ty abundant in the cotton fields, 

 and had been several times seen to catch the cotton-moth on the wing 

 and devour it. The rapacity and the capacity of these flies have been 

 seen in the quotation from Fitch ; and even supposing each individual 

 in the southern cotton fields in the course of a day to kill cotton-moths 

 in numbers that shall seem small in proportion to the number of bees 

 which Mr. Thompson actually saw them kill, we shall be obliged to put 

 them down as among the very best friends of the planter. The benefits 

 derived from the abundance of this insect will, however, be greatly de- 

 tracted from wherever bees are kept, and it is also more than probable 

 that its fondness for insects of this sort leads it to kill "wasps" and 

 "hornets," some of which, as will be shown further on, are very efficient 

 enemies of the cotton-worm. The harm done in the latter way is un- 

 doubtedly more than compensated for by the cotton- worms killed, but 

 the former habit is one which cannot be condoned, and which quite ef- 

 fectually spoils the character of these otherwise beneficial insects. 



The next order, COLEOPTERA, contains vtiy nicny pi edaceous in- 

 sects, and more species from tins order have been found to prey upon, 

 the cotton- worm than from any other. 



TIGER-BEETLES (Coleopt, fam. Cincindelidae). T.:e tiger-beetles are 

 characterized by having large heads, broader than the chest, long 

 curved jaws and long t- lender legs. They are always metallic green or 

 brown in color with purple reflections in different lights, ard are usually 

 marked with light dots and stripes. They are to be found in sunny 

 paths and sandy places. They fly and run very swiftly, and are very 

 difficult to capture. Their larvae are curious in appearance and inter- 

 esting in habits. They inhabit cylindrical holes in the ground, which 

 they probably form for .hem selves. They maintain their places at the 

 mouths ot their pits and prevent themselves from being dragged forth 

 by means of two hooks, which each carries upon the ninth segment of 

 its body, giving it a humpbacked appearance. The heads of these 

 larvae are large and flattened, and carry formidable ja*s. Stationing 

 themselves with their jaws at the mouths of their burrows, they lie in 

 wait for approaching insects, which, when near enough, they seize and, 

 retreating to the bottom of their burrows, devour. They transform to 

 the pupa state within their burrows, the mouths of which they close as a 

 preparatory step. Several species are abundant in the southern cctton 

 fields, and have been stated by correspondents to devour the cotton-worm. 

 Unfortunately, however, these insects are ground-beetles and their ca- 

 pac ty for good in this direction is limited, as they can only attack those 

 individuals which, for some reason, have fallen to the ground. 



