SUBFAM ILY VI. OECANTIIINJE. 



713 



selves. Kirby (190G, 72) recognized 27 species of the genus, 10 

 of them from America. Of these six species and one color variety 

 occur in our territory. Hart (1892) first showed that the form 

 and arrangement of the black markings on the basal joints of an- 

 tennae of Occaiitlnts furnish reliable characters for determining 

 the species, and these markings have since been used as the prin- 

 cipal differential character in all keys. 



a. 



e 



Fig. 240. Basal joints of antenrue of Occuiitliiis and Nco.vabea show- 

 ing the black markings, a, p. nivcns; b, angustipennis ; c, nigricornis; d, 

 quadripunctatus ; c, exclamation-is; f, pini: g, latipennis; It, N. bipunctatus. 



(After Lugger & Fulton.) 



KEY TO EASTERN SPECIES OF CECANTHUS. 64 



Antennas with one or more black spots on under side of the first two 

 basal segments; tegmina of male less than half as broad as long, 

 their greatest width not over 6 mm.; front of head and base of an- 

 tenna? never pinkish. 

 1). First and second basal segments of antenna? each with a single 



black mark. 



c. Black marks on both segments in the form of small round 

 spots (Fig. 240, a.) 335. NIVEUS. 



cc. Basal segment with an elongate black mark. 



d. Mark on basal segment j-shaped, hooked at base (Fig. 240, 



I).) 336. ANGTJSTIPENNIS. 



eld. Mark on basal segment club-shaped, not hooked (Fig. 240, 



e.) 337. EXCLAMATIONIS. 



&&. First and second segments each with two black marks or wholly 



black. 

 e. Head and thorax pale yellowish-green or black or marked with 



both colors. 



f. Marks on basal segment broad, often confluent (Fig. 240, c) ; 

 antenna? usually in great part black; head and thorax either 

 black or trifasciate with black; lower surface of abdomen 

 in part black. 338. NIGRICORNIS. 



S4 I have not included O. forbcsi Titus (Can. Ent. XXXIV, 260) as it was probably 

 described from a specimen with malformed palpi. Hart (Ms.) states that the unique male 

 type without the palpi is in the collection at Urbana, 111., and looks to him "like an or- 

 dinary 4-punctatiis." As far as I can ascertain only the one specimen is known. 



