ODYNEB.US. 315 



e. The yellow macula? of metathorax quite variable, forming 

 two lines or four spots, or only marking the inferior edges. 



f A yellow spot on the mesothorax before the scutel. 



g. Prothorax with a complete yellow margin or with four spots. 



h. The spots on the 2d segment very small (or wanting?). 



i. Ornaments passing into ferruginous. 



% . Unknown. 



Bess. a. diff. — This species has. quite the appearance of Ancis- 

 trocerus fulvipes and ssecularis, although without suture on the 

 1st segment. But these two species must not be taken as acci- 

 dental varieties of the same. 0. vagus has the thorax not so 

 cylindrical, shorter, a little wider anteriorly, and in the middle, 

 narrower behind; the 1st abdominal segment is more rounded, 

 more depressed at base; the 2d segment is also a little wider, 

 which makes the abdomen not so cylindrical; the whole insect is 

 not so coarsely punctured in vagus, especially on the clypeus ; 

 and the 2d segment is more finely punctured than the 1st, while 

 in fulvipes and ssecularis, the clypeus and 2d segments are 

 generally as coarsely punctured as the rest, although there exist 

 some differences in the various specimens. It greatly resembles 

 0. oculatus in. its livery, but the 1st abdominal segment is larger, 

 with more elongate yellow lines, not spots, etc. — It approximates 

 still more to 0. conformis (Comp. this species). 



Hab. United States, New York (E. Norton), Illinois (B. D. 

 Walsh), Tennessee (E. F. Falconnet). 



11T. 0. COllformis Sauss. — 0. vago simillimus, at minor, gracilior, 

 magis cylindricus, crassius punctatus ; clypeo £ crassissinie cribrato- 

 pnnctato, metanoto valde rugoso, primo abdominis segmento basi trun- 

 cato, in cantho rugoso; 20 segmento crassius punctato, margine rugo- 

 sissimo, reflexo ; niger, flavo-variegatus ; clypeo flavo-4-punctato, vel 

 fascia aut lineolis 2 flavis ; abdominis segmentis lO, 2° solis flavo-mar- 

 ginatis, IPutrinque ins uper fascia obliqua, 2°utrinque macula flava. 9 • 



Odyn. conformis Sadss. Et. Vespid. Ill, 219, 112, J var. (1854). 



Total length, 10 mm. ; wing, 7 mm. 



9. A species quite approximating to 0. vagus, but smaller, 

 more slender, more elongate, quite cylindrical, and the first abd. 

 segment longer than wide. The punctures coarse ; the ornaments 

 nearly the same. — This species still more resembles the 0. ful- 

 vipes; it has much of its elongate-cylindrical form and rugose 



