THE SHIELD-BACKED BUGS. 39 



coarse black punctures; tarsi piceous. Pronotum subhexagonal, the 

 humeral angles rounded ; disk with a vague transverse impression end- 

 ing in a deeper one each side, this extended forward nearly to front 

 angles. Scutellum with a rounded impression each side at base and an- 

 other at middle near each margin. Male with hind margin of sixth ven- 

 tral broadly concave, to receive the large semicircular genital plate. 

 Length, 12—17 mm.; width, 8 — 10 mm. (Fig. 7). 



Lake Co., Ind., and Royal Palm Park, Fla., June 15 — Dec. 18 

 (W. S.B.). Lakehurst, N. J., and Long Island, N. Y., April 

 15 — May 29 (Davis). Vienna, Va., August (Barber). Ranges in 

 this country from New York and Northern Indiana south and 

 southwest to North Carolina, Florida and Texas. Known also 

 from Mexico and recorded by Dallas (1851, 36) from Aus- 

 tralia. My Florida specimens were hibernating beneath the 

 bark of pine logs. Barber records it from six different locali- 

 ties in that State. Like most other members of the family it 

 appears to be rather scarce wherever found and occurs for the 

 most part on pine. Smith (1910, 132) states that in New 

 Jersey it : "Is sometimes found on young shoots of old pines, 

 but is especially fond of young trees. In cold weather it often 

 secretes itself among the dead needles that accumulate on the 

 upper side of the horizontal branches of pitch pine." Davis 

 (1911, 113) says that "when the legs are rubbed against the 

 file-like structures of the stridulatory areas the insect makes 

 considerable noise." 



II. Diolcus Mayr, 1864, 904. 



Species of medium size and oval convex form having the 

 head short, triangular, nearly equilateral, more or less pointed 

 in front ; tylus almost flat, slightly surpassing the cheeks ; sec- 

 ond and third antennals subequal, each two-thirds the length 

 of fourth which is slightly longer than fifth ; beak very slender, 

 reaching first ventral, its second and third joints nearly equal; 

 pronotum short, subhexagonal, its margins more or less re- 

 flexed ; scutellum as in Tetyra ; connexivum exposed for nearly 

 its full length; osteole in the form of a short tube, reaching 

 to middle of its supporting plate. Four species are recorded 

 from North America, two of which occur in the southern 

 states. 



KEY TO EASTERN SPECIES OF DIOLCUS. 



a. Punctures of upper surface reddish or purplish, those beneath few 



