June, 1843.] 277 



gard to the kind or source of sustenance preferred by the insect 

 during the time it remains above the surface. 



Dr. Morton referred to the minutes of a former year, 1834, 

 when this insect had appeared in the city and its vicinity, for a re- 

 cord of interesting information on the subject, which, at his request, 

 was read by the Secretary. 



[The following extracts from the minutes alluded to have not 

 been published at any previous period, and are presented at this 

 time, chiefly with the view of calling the attention of members and 

 others to the subject, and of inducing farther investigation. 



At the meeting of June 3d, 1834, Dr. Harlan stated that on the 

 25th of May last he had observed the Cicada septemdecim in such 

 large numbers as to blacken a field of wheat in the vicinity of the 

 city : they were also very numerous in some of the public squares- 

 It was his belief that the insect increased somewhat in size while 

 it remained ; and also, that nothing was known respecting its food. 

 Upon dissection, mere rudiments of the organs of digestion were 

 found. 



Mr. Rogers, on the contrary, stated that in 1817, the trees in 

 the neighborhood of Baltimore had been stripped of their leaves by 

 this insect. He also expressed some doubt as to their common 

 origin, from the fact of their periodical return not being necessarily 

 in the same year in different parts of the country, and that this was 

 probably owing to geological causes. 



Dr. Keagy had seen them in 1815 in the Valley of the Missis- 

 sippi ; in 1817 near Baltimore, and in 1832 in Westmoreland 

 county, Pennsylvania ; Dr. R. Coates in 1818, in Burlington 

 county, New Jersey; Mr. Gibbons in 1825, near Moorestown, 

 New Jersey, and in 1827 in the eastern part of Virginia ; Mr. 

 Johnson in 1831, near Rochester, New York; and Dr. Morton in 

 1817, in Westchester county, New York. 



Dr. Coates had seen a tree in Germantown nearly destroyed, in 

 1817, by the deposition of the ova of the insect. 

 Dr. Pickering stated that this Cicada had not yet been met with 

 in the eastern part of New England, but that a rare species of 

 Cicada had been found nearly resembling the C. septemdecim, and 

 which might be easily confounded with it; the latter differed, how- 

 ever, in the abdomen being all black: in the former, the rings of 



