MONOGKAPH OF THE NORTH AMKRICAN PKOCTOTUYPID.E. 223 



ments tlu; loiifjest, alxmt equal in length; lonrtli, the lenjjth of tho 

 tiist; tit'th, two-thirds the length of the fourth; sixth, half the length 

 of tifth; seventh very short, smooth basally; eighth subtriangular, 

 maigined. Antenna' tiliforiu, dark Itrown, the scape and iiedicel yellow; 

 second, tiiird, and the last joint of Hagelhun ahout eiiual in length; 

 first and fourtli about equal, shorter than the seeond; joints beyond 

 very slightly shorter. Wings hyaline, with a large smoky blotch below 

 the postmarginal vein; nervures fuscous; basal iiervure distinct; mar- 

 ginal uervure as long as the shaft of the stigmal, tlie latter oblique, 

 clavate at tip. 



Habitat. — St. Vincent, West Indies. 



Types in National Museum and British Museum. 



Described from 4 6 specimens collected by Herbert H. Smith. 



CACUS, K«>u. nov. Hiley. 



(Typo C. acanthi Riley.) 



" Head subtiuadrate, emargiuate behind, the occiput feebly margined ; 

 ocelli 3, triangularly arranged, the lateral close to the eye; eyes ovate, 

 bare. 



*'Antenna? inserted at the clypeus, 12-jointed in both sexes; in 5 cla- 

 vate, the club G-jointed, the last funicular joint usually transverse, the 

 otliers longer than wide; in S flliform, the third funicular joint a little 

 dinted and emarginate toward base. ' 



"Mandibles short, either tridentate or bifid at tip. * 



"Maxillary palpi 3-jointed; labial i)alpi li-jointed. 



"Thorax ovate, narrowed before, the prothorax slightly visible from 

 above; mesonotum most frequently without furrows, rarely with dis- 

 tinct furrows; metathorax not especially short, Avith two lateral keels, 

 a median prominence or carina, and with usually two small erect teeth 

 at apex, above the insertion of the abdomen. 



"Front wings with the submarginal vein joining the costa a little be- 

 yond the middle of the wing, the marginal vein variable, scarcely half 

 the length of the stigmal, or much longer; the latter oblicjue, termi- 

 nating in a knob; the postmarginal vein very long, the basal vein sub- 

 obsolete, 



"Abdomen much as in Barycotius, but the female without the horn- 

 like projection at base. 



"Legs as in Baryconus, the tibial spurs 1, 1, 1, the middle and hind 

 pairs weak, tarsi long and slender, the basal joint more than four times 

 the length of the second." — [From Rileyh M8.\ 



It is probable that under this genus Dr. Riley has included two distinct 

 genera, one distinguished by having 3 dentate mandibles, the other in 

 having the mandibles bifid or 2-dentate, but otherwise they are so 

 similar that for the present I believe it best to follow him in consider- 



