172 ENTOMOLOGICAL NEWS. [April, '15 



lower pair of which are the larger. Gonapophyses small, pale, feebly 

 chitinized, cylindrical, on the cephalic face at two-thirds the length 

 with a feeble chitinized tooth. 



Habitat. Eastern United States and Canada. 



Holotype, $, Sacandaga River, Fulton Co., N. Y., June 26, 

 1914 (Alexander). 



Allotype, 9 , topotypic. 



Paratypes, 30 $ , ? , topotypic. 10 $ , 5 , Truro, Nova Sco- 

 tia, July 7 to 26, 1913 (Matheson). 



This interesting species has long been confused with 

 Gonomyia cognatella O. S., but has little in common with that 

 insect. It is more closely related to G. blanda O. S., but is 

 easily separated by the unmarked wings. The cell ist M 2 open 

 by the atrophy of the outer deflection of vein M 3 is found 

 only in cognatella, blanda and mathesoni in Eastern North 

 America. These three species may be separated as follows: 



1. Basal deflection of Cui at the fork of M ; Sc short ending just 

 before the origin of Rs. cognatella O. S. *. 



Basal deflection of Cui far before the fork of M; Sc long, ending 

 beyond the origin of Rs. 2. 



2. Wings spotted. blanda O. S. f. 

 Wings unmarked. mathesoni sp. n. 



This species is named in honor of the collector of the para- 

 types from Nova Scotia, Dr. Robert Matheson, of Cornell 

 University. 



The insect, both in New York and in Nova Scotia, is found 

 on rich vegetation along the banks of rivers. The Tipulidae 

 found in association with this species include the following: 

 Antocha sa.ricola O. S., Cryptolabis paradoxa O. S., Rhabdo- 

 masti.v (Sacandaga) nava Alex., Gonomyia sulphur ella O. S., 

 etc. 



* cognatella Osten Sacken; Proc. Acad. Nat. Sci., Phila., 1859, 230; 

 Monographs of the Diptera of North America, IV, 1869, 181, pi. IV, 

 fig. 18 (male genitalia) ; 23rd Report N. Y. State Entomologist, 1907, 

 Needham, Crane-flies of New York, pi. 24, fig. 4 (wing). 



f blanda Osten Sacken; Proc. Acad. Nat. Sci. Phila., 1859, 231; 

 Monographs of the Diptera of North America, IV, 1869, 182, 183, pi. 

 IV, fig. 17 (male genitalia) ; 23rd Report N. Y. State Entomologist, 

 1907, Needham, Crane-flies of New York, pi. 24, fig. 5 (wing). 



