ZETIIUS. 33 



% . Clypeus trans.ver.se quadrate, either wholly pale-yellow, or 

 only its lower part; inferior margin entire and arcuate ; the last 

 two artieles of the antennae tawny beneath. 



Var. a. Two yellow spots on the scutellum. 



b. The yellow mark of the frontal ridge and that on the post- 

 seutel, interrupted; the face presenting but two yellow points. 

 The border of the prothorax is sometimes sprinkled with black 

 dots. 



c. The yellow markings hardly visible. Prothorax black. 

 Legs black; wings a little smoky, with some ferruginous tints and 

 the nervures brown. 



d. The spine of post scutel yellow or black. 



e. In small specimens, principally % , the spine is obliterated, 

 or replaced by a little longitudinal carina. 



f. The peduncle of the 2d segment rather longer; the spine 

 of post-scutel obliterate. 



g. The extreme edge of the ctypeus % black, or partly black, 

 which causes very fallacious appearances. 



Ress. a. diff. — This species is very distinct, by its ridges, 

 prominences, and rugosities, by the very large punctures of its 

 petiole, and especially by the long spine of its post-scutel. 



Bab. The gulf side of Mexico, in the warm parts. Tamaulipas, 

 Iluasteca, etc. Very common in Tampico. I have taken a score 

 of specimens in view of the town of Pueblo-Vicjo, against posts 

 exposed to the sun. Various specimens also from Orizaba. 



Fig. 2. The insect seen in profile, enlarged. 2,6. Its natural size. Fig. 

 2, a. The abdomen more enlarged. 



20. Z. imitator n. sp. — Niger, crasse, dense pnnctatns: metanoto 

 minus crasse punctato ; petiolo ovato-cylindrico. crassissime cribrato ; 

 punctis 2 clypei ; 2 frontis, pronoti margine, macula subalari, tegnlaram 

 limbo, scutelli fascia interrupta, post-sontelli fascia, inaculis 2 metanoti, 



abdominis segmentorum l°-3° limbo anguste, tibiisque intermediis basi 

 extus, tlavis. 9 • 



Total length, 12.', mm.; wing, 9 mm. 



9. Form and sculpture about the same as in spinosus. Head 

 small. Clypeus much rougher, very coarsely and confluently 

 punctured, not broad, but rounded, more prolonged ami truncate. 

 A carina, between the antennae, prolonged on the clypeus. The 



rest of the punctuations about the same, wry rough. Prothorax 

 3 



