284 MYMENOPTERA. 



segments having a round spot of white pubescence at their ex- 

 treme lateral margins. 



Hab. Para. (F. Smith's Coll.) 



Genus 37. CTEKIOSCHELUS. 



MeUssoda, St.Farg. Hym. ii. 508 (not of Latr. 1841). 

 Isehnocera, Shuck. Hist. Ins. Lardner Ency. (1840). 

 Ctenioschelus, Romand, Mag. Zool. (1841). 



Antennae of the females filiform, the apical joint compressed, 

 rounded at the apex. The maxillary palpi composed of a single 

 joint; the labial palpi four-jointed, the basal joint elongate, the 

 second scarcely one-third the length of the first ; the two apical 

 joints minute, placed at the side of the second at its apex ; the 

 tongue elongate, twice the length of the labial palpi. The supe- 

 rior wings having one marginal and three submarginal cells ; the 

 former about the length of the three latter, rounded at its apex ; 

 the first recurrent nervure uniting with the second transverse 

 cubital nervure ; the second recurrent nervure received near the 

 apex of the third submarginal cell. The intermediate tibise armed 

 at their apex with a single spur, which is furcate at the aj^ex ; the 

 anterior spine of the furcation having three acute teeth or spines 

 on its posterior margin; the spines at the apex of the posterior 

 tibiae simple. In the males, the antennae are longer than the 

 body, the four apical joints being clavate, and the apex of the 

 abdomen spinose. 



1. Ctenioschelus Latreillii. B.M. 



Melissoda Latreillii, St. Farg. Hym. ii. 508. pi. 16. f . 3 ^ . 

 Ctenioschelus Goryi, Romand, Mag. Zool. 1841, p. 4. pi. 69. f. 1 <? , 



Female. — This sex is rather larger than the male, but similar 

 in colour, and having a similar calcar on the intermediate tibiae ; 

 the abdomen is acute at the apex, and without spines ; the third, 

 fourth and fifth ventral segments of the abdomen have laterally 

 on their posterior margins a patch of silvery- white pubescence. 



Hab. Monte- Video; Paraguay; Brazd. 



Genus 38. ACANTHOPUS. 



Apis, pt., Fabr. Ent. Syst. ii. 316 (1793). 

 Xylocopa, pt., Fabr. Syst. Piez. p. 339 (1804). 

 Acanthopus, Klug, lllig. Mag. vi. (1809). 



The labial palpi four-jointed, the two apical joints minute ; 



