AQUATIC INSECTS IN NEW YORK STATE 2G7 



Qomphus furcifer 



Mr T. H. Hankinson took a specimen of this species on the 

 Renwick flats at Ithaca in July 1901, thus establishing the fact 

 that the species belongs to the Ithaca fauna. 



Gomphus notatus 



This species and G. p 1 a g i a t u s are very closely related. 

 Both are likely to be found in the State eventually. I have 

 recently had bred specimens of notatus for study from the 

 United States National Museum, and from Mr E. B. Williamson, 

 the former from Detroit Mich, and the latter from Nashville 

 Tenn. The differences between the nymphs of the two species 

 are so slight that they will be appreciated with difficulty by a 

 novice. They are as follows: (1) In notatus the ninth 

 abdominal segment is more than five times as long as the tenth 

 segment ; in p 1 a g i a t u s , less than five times as long. (2) The 

 two to three obliquely truncated teeth on the inner margin of the 

 lateral lobe of the labium are twice as big in notatus as in 

 p 1 a g i a t u s [see Bui. 47, pl.20, fig.l6]. (3) The rudiment of a 

 dorsal hook on the apex of the ninth abdominal segment is a 

 little better defined in notatus. 



Gomphus spiniceps 



A nymph of this species was taken from Forest lake, Ithaca, 

 liy Mr O. A. Johannsen, in July 1002, and reared. 



Gomphus descriptus 



Corrections. In Bulletin 47, page 454, there are stated to be six 

 to eight teeth on the inner margin of the lateral lobe of the 

 labium of the nymph of this species; the number should be eight 

 to ten as given in the key on page 446. 



On page 436 the word " tarsi " in line aa in the key at the 

 bottom of the pa^e should read " femora." 



Cordulegaster sayi 

 I have received nymphs from Mr C. S. Brimley of Raleigh 

 If. C. that should belong to this species, because of their locality 

 and their very close resemblance to those of C. d i a s t a t o p s. 



