FA M ILY VII. TETTIGON I IDAS. THE KATYDIDS. 



as deep, both their hind and lower margins oblique and meeting in a 

 rounded angle; humeral sinus distinct but broad and rather shallow (Fig. 

 184, (I.) Tegmina surpassing hind femora about 2 mm., exceeded by wings 

 3 mm., those of female strongly reticulate. Hind femora rather short and 

 stout, armed beneath with one to four very short spines. Cerci as in key 

 and Fig. 183, f, the tooth with base broad and flat. Apex of subgenital 

 plate subtruncate, styles short and very slender. Ovipositor very similar 

 to that of 0. gladiator, being very long and stout, nearly straight above, the 

 under side regularly curved, its apical third sloping rapidly to an acute 

 apex. Length of body. $, 17 20, $, 2025; of pronotum, $, 3.74.5, 9, 

 45; of tegmina, $, 19 24, 9, 24 30; of hind femora, $, 15 16.5, 9, 

 17 19 ; of ovipositor, 9- 10.5 mm. 



In Indiana rolantuni has been taken in A 7 igo, Fulton, Marshall 

 and Starke counties. It is found most abundantly during August 

 and September on the leaves and stems of a tall, broad-leaved knot- 

 weed, Polygonuin ainphibnun L., which grows luxuriantly in the 

 shallow waters about the margins of the larger ponds and lakes. 

 Several other "green grasshoppers," notable among which are 

 Conocephalus attauiatus (Scudd.) and OrclieUmmu nl gripes 

 Scudd., frequent this plant in large numbers. Keeping company 

 with them an occasional specimen of 0. rolantinu is seen, but, 



Fig. 187. a, Outline of stridulating field of male of O. militarc; b, same of O. rolan- 

 tinii, X 3; c > outline of male type of O. bradlcyi, X i-8. (After R. & H.) 



being an active leaper, it often escapes amidst the dense foliage 

 of the knot-weed before its capture can be effected. Its less ro- 

 bust body, longer armed posterior femora and long tegmina readily 

 distinguish the female of this species from 0. gladiator, the only 

 other Indiana form which has an ovipositor shaped like that of 

 rolanhuii. The 0. hrum-ri Blatchley (1893c, 02) is a synonym. 



The known range of typical 0. volantinn is rather limited, ex- 

 tending from Sarnia, Out., and northern Ohio west to eastern 

 Nebraska and south to central Indiana and Douglas Co., Kansas. 

 McNeill (181)1,) took his types "from a clump of rank growing 

 Xagittaria rariabilix Englm., on the banks of Rock River, Henry 

 Co., 111., being attracted to them by their peculiar stridulation." 

 Their song, he says, "had a new note in it and may be represented 

 as follows: .:/>-.://>. Jcr-zc-c-c, l>r-.:c-c-c, the last part of the song not 

 lasting more than a half to three-quarters of a second and always 

 preceded by the sound which I represent imperfectly by AT." 



