ZETHUS. 23 



fine submarginal sulphur-yellow line on the 2d segment. The 

 antennas quite black. 



% ■ Clypeus flattened, only delicately punctate-strigate, a little 

 trilqbed in the middle of its inferior margin; metathorax not so 

 much hollowed posteriorly; a little strigate on sides; the exca- 

 vation not margined at top ; the lateral carinse very sharp and 

 prolonged nearly down to the end, not obsolete beyond the angle ; 

 the lateral faces polished. The swelling of the petiole not go 

 oval, but more attenuated posteriorly; the second segment more 

 pediculate, so that it might be almost classed in the Division 

 Didymogastra. 



The body is not clothed with golden silky hair, but only with 

 a little grayish pubescence on the metathorax and abdomen ; the 

 face or clypeus not silvery as in Z. aztecus. 



%. Antennae black; all the joints of the flagellum annulated 

 beneath at their base with pale-yellow; the first joint having its 

 macula near the end ; the scape black. Clypeus broad, quad- 

 rangular, transverse, whitish-yellow, not silveuy; its inferior edge 

 black, widely emarginate, with 2 distant teeth. The intermediate 

 tibiae ornamented before with a white line, running over the first 

 joint of the tarsi. 



Hab. Mexico, the 'eastern Cordillera. Orizaba (Mr. Sumi- 

 chrast). 



This species has the appearance of Z. Jurinei, because of its 

 oval petiole being posteriorly attenuated, and its black shining 

 color, but it is smaller ; its petiole is not impunctate, polished, 

 etc. 



b. Swelling of the petiole cylindrical. 

 * Metatliorax not excavated, 



13. Z. Heydeili n. sp. — Niger, pnnctatus, tomento aureo ubique ves- 

 titus ; pronoto cristato-marginato, sed angiitis baud spinosis ; petioli 

 tumore cylindrico, snbdepresso ; corpore maxime flavo-variegato ; 

 abdominis seginentis omnibus tenuiter flavo-limbatis ; pedibus flavis, 

 femoribus nigro-variis ; alis pellucidis, venis ferrugineis. 



£ . Mandibulis et clypeo flavis ; hoc in medio margine producto-truncato ; 

 antennis Julvis sub scapo fascia flava, apice cocbleatis. 

 Total length, 16 mm. ; wing, 11 mm. 



?. Insect slender. Head wider than high, densely cribrose. 

 Thorax densely cribrose ; prothorax strongly flanged, but the 



