54 E. T. CRESSON. 



3. Calcaria black or fuscous 4. 



Calcaria pale 5. 



4. Yellow spots on posterior i)art of second abdominal segment oblique, basal 



spots long, linear; sides of thorax rounded between the two notches; 



tibife and tarsi outwardly mostly black 81. Iliaiica. 



Yellow spots slightly transverse, rounded or subquadrate. basal spots short, 

 ovate: sides of thorax prominent and tuberculate between the two 

 notches; legs with pale pubescence, calcaria black or fuscous. 



82. sodalis. 



5. Yellow spots on posterior part of second abdominal segment oblique. 



83. optatn. 

 Yellow spots transverse. 

 Sides of thorax deeply notched ; legs with pale pubescence- . • -84. borba,. 

 Sides of thorax not or scarcely notched. 



Tibi?e and tarsi outwardly mostly with black pubescence: no pale pubes- 

 cent spot on apical middle of second abdominal segment. 



85. jiiveiialis. 



Legs with pale pubescence; a small pale pubescent spot on apical middle 



of second segment 86. auxiliaris. 



87. M. nnimarginata 9.— Length 14-15 mm.— Head transverse, as wide 

 as thorax ; eyes very convex, smooth, polished : thorax gradually narrowed pos- 

 teriorly, lateral margin rather deeply constricted before metathoracic stigniatic 

 tubercles, which are prominent; sides of metathorax coarsely rugose, the poste- 

 rior face flat and rather abruptly declivous; abdomen ovate, first segment small, 

 slightly widened to apex, which is somewhat constricted transversely, the base 

 with the usual compressed tooth on each side, which appeare acute when viewed 

 from above; second segment rather closely and coarsely punctured. 



Velvety black, with black pubescence: head entirely black above, cheeks with 

 pale hair; scape of antennte with golden puljescence ; thorax above with two 

 broad entire cupreous pubescent stripes, which are pale at apex of metathorax, 

 flanks with patch of dense silvery pubescence on lower portion ; legs with pale 

 glittering hair, calcaria black or fuscous; sides of first segment pale golden ; a 

 narrow band, longitudinally grooved on disk, near apex of second segment, and 

 two narrow elongate spots at base yellow, smooth and polished ; a silvery stripe 

 on middle of remaining segments beginning at apex of second, and a silvery spot 

 on extreme sides of segments 2-4 ; venter with long pale hair, dense at apex of 

 segments 2-4. 



Chapada. A very distinct species, easily recognized by the nar- 

 row yellow band at apex of second segment of abdomen, and the 

 two broad cupreous stripes on thorax. 



88 M. luiiiidiila 9- — Length 11 mm. — Closely resembles unimarginata, 

 but difl'ers by the smaller size, by the two stripes on thorax being narrow and 

 silvery, and the pale calcaria; in two specimens there is a small silvery spot on 

 vertex, and in the other the face is pale golden ; the yellow spots at base of 

 second segment are wanting, except in one specimen, where they are very small. 



Chapada. Three specimens. 



