October 1S94.' 



psrcHE. 



153 



Form Iriaiigularii Sciidd. 



Tettix triangularis Scudder, 475. 

 " " Scudd. Thomas, 1S5. 



" " " Fernald, 47. 



" " " Bolivar, 25S, 265. 



" " " Morse, 54, 107. 



This is a very variable species in 

 both structure anil ornamentation and 

 has consequently been described under 

 several names, while an unfortunate 

 typographical or mechanical error has 

 caused further confusion. Scudder, in 

 the original description oi triangularis 

 gave the length of the pronotum as .17 

 inch; this has been copied by Thomas, 

 Fernald, and Bolivar, and perhaps 

 others. This is just one-half its usual 

 length in that form, and the error ^vas 

 quite likely of mechanical origin. 

 Bolivar evidently describes this form 

 under the name of ornatits while 

 doubting the specific distinctness of 

 triangularis which was unknown to 

 him ! At least, this seems to be the 

 onlv interpretation possible to place 

 upon his table of species and the 

 dimensions given under T. ornatus. 



Description^ etc. — Tlie following measure- 

 ments will be of interest in this connection. 

 I believe that the two forms are but one 

 species, as stated in Psyche, 1894, p. 54, 

 since they are indistinguishable except in 

 length of pronotum and wings, and inter- 

 grade in those particulars, and so have not 

 attempted to keeji their measurements 

 separate. 



Total Unglh. Pron. Proii.> Hind /em. IV'^s. vr. Proii . 

 crS.3-12.5 7.5-lo.S 0-3.4 — .5-+1. 



?9--li-5 8. -12. 0.-3.5 _.5-+,.5 



As is here shown the pronotum is very 

 variable in length, in some only reaching the 

 end of hind femora, in others passing it by 

 3.5 mm. ; and the wings are equally variable, 

 and usually least developed proportionally 

 in those specimens with the shortest pronota. 

 It is impossible to draw any line between the 

 two forms ornatus and triangularis, although 

 the typical forms are quite distinct. Of 124 

 specimens in my collection a little over two- 

 iifths are nominally referred to the trian- 

 gularis form, and the se.\es are evenly 

 divided in both forms. Nor is there any 

 difTerence in seasons or haunts. 



The species is readily recognizable from 

 the characters of the vertex. This projects 

 in front of the eyes, is somewhat rounded 

 anteriorly and the mid-carina forms a distinct 

 projecting tooth. The profile is rounded- 

 angulate above, excavate opposite the eyes 

 and protuberant opposite the antennae. 

 Very rarely a specimen is met which in a 

 dorsal or a profile view approaches T. 

 granulatus closely, but any doubt of its 

 identity is usually dispelled by an examina- 

 tion of it from both directions. 



Habits, etc. — This species is found 

 most commonly in moist sedgy meadows 

 and swales, often in company with T. 

 granulatus, but is also frequenth' met 

 with in damp places on drier grounds, 

 uplands, etc. At no time plentiful, it 

 seems to be most common in spring 

 antl fall but I have captured it in everv 

 month from April to October. I have 

 specimens from Fryebin^g, Me., Aug. 

 30, Hanover, N. H., Sept. (C. M. 

 Weed) , Newport, and Jay, Vt.,-Juh- 13, 

 15, Brattleboro, Vt., April 17-May 14 

 (Mrs. J. B. Powers), New Haven, 

 Conn., Aug. 29, Beverly, Mass., April 

 24, Green Lodge Sta., Jinie 14, Slier- 



