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I 



believed to probably be the same species. Since the publication of 

 that report in 1868, the same species lias received frequent mention in 

 reports and other publications of Dr. Riley, as also by many other 

 economic entomologists. The species has in some way gained general 

 credit for being efficient as a destroyer of injurious insects, but, to the 

 best of the writer's knowledge, its exact economic status has never 

 been clearly defined. The observations which will be here presented, 

 although not bearing upon this subject to any considerable extent, are 

 of interest as being, perhaps, the first actual observations on the living 

 habits of the larva. From the fact that the larvae were found so deep 

 under ground, and in the absence of other species that might have 

 served for food, it would seem not improbable that they subsist to a 

 considerable extent upon angleworms rather than on the larvae and 

 pupae of other insects. A comparison with the illustration and descrip- 

 tion of the larva mentioned in the First Missouri Report and used the 

 same year in the American Entomologist (Vol. I, p. 34), show that this 

 is not Harpalus pennsylvanicus, the color alone being sufficient to 

 exclude it, but is perhaps Pterostichus or a related genus, as pointed 

 out in volume Y of Insect Life (p. 209). The species treated by Riley 

 in the First Report of the U. 3. Entomological Commission (p. 290, fig. 

 24) is, however, plainly a Harpalus, or at least a closely related genus, 

 and perhaps H. herbivagus Say, a smaller species than pennsylvanicus, 

 and undoubtedly differing to a considerable extent in structural details 

 and, perhaps, also in habits, judging from the fact that the hypothetical 

 herbivagus is much darker than pennsylv aniens. The latter is nearly 

 white throughout, indicating an almost exclusively subterranean habit. 

 April 8, 1898, while preparing a little plat of earth for experimental 

 purposes on the Department of Agriculture grounds a single larva 

 and two adults of Harpalus pennsylv aniens DeG. were found by Mr. 

 F. 0. Pratt at a considerable depth below the surface. The digging of 

 the earth began at the southeastern corner of the grounds and pro- 

 ceeded northward, the work extending over portions of three days. 

 On the second day numerous pupae and only a single larva wei e found, 

 and on the third day in the northern end of this plat, which was bor- 

 dered at this side by a driveway and high hedge of evergreens, an 

 abundance of larvae were taken, with only one or two pupae. The last 

 larvae dug up were the smallest and least mature. The most mature 

 individuals were found on the southern end of this plat and the least 

 mature on the northern end. Still another point was noticed, namely, 

 that the insects occurred for the most part within about 2 or 3 feet of 

 an Osage-orange hedge nearest the sidewalk. Nearly all of the larvae 

 and pupae dug up — about 40 in number — were found at a depth of 9 or 

 10 inches, and with the exception of three individuals — beetles and 

 larvae taken on the first day — were within about 20 feet of the hedge 

 and trees bordering the driveway. These details, although, perhaps, 

 inconsequent in themselves, are mentioned, as the occurrence of the 

 insects in the manner narrated was as noticeable as it is unexplainable. 



