270 FAMILY VIII. — CORIZID^. 



middle of fourth segment of dorsum. Fracker (1918, 276) has 

 given the varietal name cinereus to the paler form. 



Family VIII. CORIZIDJE Mayr, 1868, 121. 

 The Scentless Plant Bugs. 



Small or medium sized oval or oblong-oval species possessing 

 the majority of the characters of the Coreidse but having the 

 head always triangular, narrowed and more or less projected 

 forward in front of antennse; basal joint of antennae always 

 shorter than head, the terminal one thicker than the second 

 and third ; apex of corium straight or nearly so ; fourth dorsal 

 segment of abdomen sinuate at middle on both the front and 

 hind margins, or at least on the hind one, where the sinuation 

 receives a median forward-prolonged lobe from the fifth seg- 

 ment ; osteolar openings in our species obsolete ; sixth ventral 

 of female not slit at middle. 



The species are, for the most part, of small size and pale in 

 color and occur, often in numbers, in late summer and autumn, 

 upon weeds and other plants growing in open fields and along 

 the borders of woods and roadsides. The family is by Stal and 

 Van Duzee treated as a subfamily of the Coreidse, but by more 

 recent writers as a distinct family. Van Duzee, in his Cata- 

 logue, recognizes three tribes, six genera and 29 species from 

 the United States. Of these all the tribes, five of the genera 

 and 16 of the species are represented in the eastern states. The 

 principal available literature most useful in the study of the 

 family is as follows : Stal, 1870, 1873 ; Hambleton, 1908 ; Baker, 

 1908; Torre Bueno, 1912a; Gibson, 1917a, 1919. 



KEY TO TRIBES OF CORIZID-F. 



a. Hind femora spined beneath; front angles of pronotum prolonged 

 forward in an acute spine. Tribe I. Harmostini, p. 270. 



aa. Hind femora unarmed beneath; front angles of pronotum obtuse, 

 unarmed. 

 b. Head abruptly narrowed behind the eyes into a distinct neck; side 

 margins of pronotum entire; general color pale; smaller, length, 

 not over 9 mm. Tribe II. Corizini, p. 276. 



bb. Head not narrowed behind the eyes; side margins of pronotum 

 notched near front angles ; general color black with red mark- 

 ings; larger, 11 or more mm. Tribe III. Leptocorini, p. 283. 



Tribe I. HARMOSTINI Stal, 1873, 97. 



Small oblong-oval species having the head porrect, broader 



