1910.] NATURAL SCIENCES OF PHILADELPHIA. 431 



that of pronotum; apex very slightly rotundato-angulate ; costal 

 field moderately broad, translucent. Wings with four to five complete 

 and one to three incomplete rami to ulnar vein. Supra-anal plate 

 subtrigonal, with median portion narrower than in I. pensylvanica, 

 more decidedly concavo-emarginate laterad; cerci depressed, monili- 

 form, slightly fusiform. 



General color much as in /. pensylvanica but with lighter shades 

 on pronotum and tegmina much paler, subhyaline cream-buff, humeral 

 trunk very narrowly indicated. Discal maculation on pronotum as 

 in pensylvanica but frequently with pale medio-longitudinal dividing 

 line, maculation vandyke brown. Venter prout's brown, occasionally 

 bistre cephalad, limbs similar to venter but in part at least slightly 

 paler; supra-antennal spots yellowish; antennae of ventral color. 

 Pale border on pronotum occasionally buff. 



9. Size medium; form much as in same sex of /. pensylvanica. 

 Head with but extreme occiput visible cephalad of pronotum; inter- 

 space between eyes but slightly less than that between antennal 

 s3robes; antennae very slightly longer than body. Pronotum semi- 

 elliptic, cephalic and lateral margins regularly arcuate, caudal margin 

 arcuato-truncate, caudo-lateral angles rounded rectangulate, greatest 

 length about two-thirds greatest width; disk deplanate, lateral 

 portions considerably deflected. Tegmina about one and two-thirds 

 times length of pronotum, apices reaching to third abdominal seg- 

 ment, sublanceolate, subacute, costal margin regularly and con- 

 siderably arcuate; costal field rather short, comparatively broad, 

 anal sulcus joining sutural margin slightly distad of middle of latter, 

 costal veins regular, obliquely parallel. Wings aborted, functionless, 

 not reaching caudad of first abdominal segment. Supra-anal plate 

 trigonal, margins concavo-emarginate, apex well rounded; cerci 

 depressed fusiform. 



General coloration much as in /. pensylvanica but paler; pronotal 

 maculation indicated more or less distinctly 17 

 by a hazel wash, occasionally clouded with 'ST/ 7 ' S \~/ 7 ' 

 bistre and frequently divided medio-longitu- 



dinallv. margins buff or ochre yellow; tegmina Figs. 13 and 14.— Isch- 



, noptera divisa S.-Z. 



ochraceous, tawny ochraceous or raw umber. Supra-anal plate of 



subhyaline costad; abdomen olive to clove d , (X5)aiid 9 (X4). 



brown, margined laterad with buff or clay color; 



limbs pale ochraceous, spines and carinas burnt umber; face usually 



17 Almost lacking in one specimen (Rives, Tenn.) which has the disk ochre 

 yellow and margins almost hyaline. 



28 



