113 H NOV 19 1954 



condition only In caverns ; a myriopod of the genus Polyctesmua^- 

 also white ; and an arachnid, belonging to the group of har- 

 vestmen, and to a genus, Nemastoma, not before known to 

 the new world. Besides these there occurred a small white 

 mollusk of a form hitherto unknown. He also explored a cave 

 near Manitou, in Colorado, and found there a beetle, Dlclidla 

 laetula, which occurs near the mouth and also in the open air 

 under stones ; and a fly, Blepharoptera defessa, which had been 

 taken before in Kentucky caves. 



This brings me to the final division of my subject, the biolog- 

 ical results of the investigations of injurious insects. A proper 

 analysis of all that has been done in this field is manifestly a 

 work of great difficulty, for over three hundred octavo pages 

 have appeared during the past year in official documents or 

 scientific journals on the destructive locust alone, without 

 counting Mr. Riley's book of two hundred and thirty-one 

 pages, which is a reprint of a part of the material above esti- 

 mated, together M-ith some taken from his previous reports. I 

 cannot attempt to treat this portion of my subject in detail, but 

 will content myself with a simple statement of what insects 

 have been discussed, and close with a brief account of what has 

 been done upon the natural history and ravages of Caloptenus 

 spretus. 



With the exception of Mr. A. R. Grote's account of a species 

 of Nephopteryx which injures pine trees by boring into the 

 bark and wood and thus causing an exudation of the pitch, all 

 papers which pretend to offer anything new upon injurious in- 

 sects, other than the locust, were written by the members of 

 the U. S. Entomological Commission. Of these three natural- 

 ists, however, Mr. Cyrus Thomas, in his Illinois report, has 

 contributed no new observations that I can discover, excepting 

 upon the army worm, Leucania unipuncta ; this he regards as 

 normally a cut-worm, believing that he has found it living in 

 early life upon the heads and blades of grain, and at its final 

 stage "workino; beneath the grass and remainino- hid from view," 

 The evidence upon which he bases this extraordinary state 

 ment is, however, as his own words show, purely a matter of 

 inference, and has no scientific basis. 



