12 



was the hatching this year of the eggs of the Rocky Mountain Locust or Western Grass- 

 hopper, CaJoptenus spretus, that were laid in 1376 around the Agricultural College at 

 Manhattan, Kansas. These eggs were buried some ten inches below the surface in the 

 fall of 1876 in grading the ground around the chemical laboratory, the superincumbent 

 material being clay, old mortar and bits of stone, and a plank sidewalk above this. 



In removing and regrading the soil last spring, Mr. J. D. Graham noticed that tho 

 eggs looked sound and fresh, and that they readily hatched when exposed to normal 

 influences j the species being determined by Prof. Riley from specimens submitted by Mr. 

 Graham. Remarkable as the facts are, there can be no question as to their accuracy, so 

 that the eggs actually remained unhatched during nearly four years and a half, or four 

 years longer than is their wont. This suggests the significant question : how much 

 longer the eggs of this species could, under favoring conditions of dryness and reduced 

 temperature, retain their vitality and power of hatching 1 



Putting all the facts together. Prof. Riley concludes that we are yet unable to ofFei' 

 any satisfactory explanation of the causes which induce exceptional retardation in devel- 

 opment among insects. The eggs of Crustaceans, as those of Sepus and Cypris, are known 

 to have the power of resisting drouth for six, ten or more years without losing vitality, 

 while in some cases they seem actually to require a certain amount of desiccation before 

 they will hatch. Yet the fact remains that different species act differently in this respect, 

 and that individuals of the same species, under like external conditions of existence, act 

 differently ; that temperature, moisture, food, etc., do not influence them alike. We can 

 understand how this great latitude in susceptibility to like conditions may, and does in 

 the case of exceptional seasons, prove beneficial to the species by preserving the exceptional 

 individuals that display the power to resist the usual changes. 



The next paper was by the same author, on New Insects injurious to American Agri- 

 culture, in which attention was called to several insects hitherto unknown as injurious, 

 which during the present year have proved very destructive to one crop or another. Such 

 hitherto unknown and unreported injury is either caused by — 1st, imported species; 2nd, 

 native species previously known, but without destructive habit ; 3rd, unknown or unde- 

 scribed species. 



Mr. W. H. Edwards then read a paper on certain habits of Heliconia charitonia. 



Some interesting discussion followed the reading of these papers, after which an 

 informal discussion on Entomological subjects took place, in which many of the members 

 joined. The meeting then adjourned. 



On Friday, at 11.30 a.m., the Entomological Sub-section held another session. 



The first paper, " On the Length of Life of Butterflies," was read by W. H. Edwards, 

 followed by one on the Life Duration of the Heterocera, by J. A. Lintner, both of which 

 will appear in the pages of the Entomologist. 



A few remarks were made by C. V. Riley on his own extended observations on the 

 duration of the lives of both butterflies and moths, indicating that they were, as a rule, of 

 very short duration. 



Cyrus Thomas stated that according to his observation the Army Worm, as a cater- 

 pillar, a chrysalis and a moth, existed in all seventy-seven days. Some observers had, 

 however, made it seventy-six, others seventy-nine days. He contended that in confine- 

 ment, in a proper temperature and with ample food, the Army Worm passed through its 

 metamorphosis more quickly than in natural conditions. 



B. P. Mann disagreed with Mr. Thomas on this latter ; so also did C. Y. Riley, it 

 being contrary to their experience. 



J. A. Lintner, State Entomologist of New York, then read a paper on "A Remark- 

 able Invasion of Northern New York by a Pyralid Insect." 



He said that about the middle of May, of the present year, a serious invasion of St. • 

 Lawrence County, N. Y, and several of the adjoining counties, by the "Army Worm" 

 X was announced. It was stated that many pastures had been completely ruined, and the 

 entire destruction of the pastures and meadows was threatened. Not having witnessed 

 the operations of the Army Worm, he at once visited the infested locality. The reports 

 had not been exaggerated. The injury was widespread and serious, already extending 

 over eight of the northern counties. Hundreds of acres of grass presented a brovvn 



