1865;] 373 



Antennal joint 4 but little more than half the 1 



length of the third: antennae ( 9 ) 13-jointed ; [ „ „ .. „ _ 



mesonotum entirely black, the yellow being [ "gmcola U. B. % 9 . 



strictly confined to the collare. J 



3. Mesonotum with coarse, transverse, ridge-like rugosities, giving it a 



rough appearance 4 



Mesonotum with fine transverse wrinkles, preserving, however, a 

 smooth appearance 5 



4. All the feet partly infuscated: antennae ( 9) 14-1 



jointed, nearly as long as the body; the se- [ _ _ , w , , n 



cond abdominal segment seen from the side f '' & - menaax VValsn V- 

 is distinctly longer than broad. J 



The hind tibiae and the basis of the hind tarsi] 

 alone are infuscated : antennae ( 9 ) 13-jointed : | 



the second abdominal segment. ( 9 ) seen from j. 5 _ g di hus . S. % ? 



the side, is but very little longer than broad: f r u + 



thorax of 9 black; in the % the pleurae and I 

 the head are yellow. 



5. Second abdominal segment, ( 9 ) seen from the ) 



side, much longer than broad, attenuated to a V 3. S. laeviventris 0. S. 9 • 

 point at the tip, almost lanceolate. J 



Second abdominal segment ( 9 )> seen from the side, but little, or not 



longer than broad 6 



6. Long ( 9 )• ventral valve considerably projecting. .6. S. albipes Walsh, % 9 • 



Long ( 9 )> ventral valve usually concealed 4. S. campanula 0. S. 9 • 



1. Synergus oneratus Harris. 

 Syn. Cj/nips oneratus Harris, Ins. etc. 3d ed. p. 54S. Fitch, Eep. etc. II, No. 313. 

 This species (0.12 — 0.14 long) is variable in coloring, the black stripe 

 in the middle of the thorax and of the head having more or less ex- 

 tent ; in some specimens the head has no black spot at all, and the 

 stripe on the thorax is also obsolete. It is distinguished from the fol- 

 lowing species: 1st, by its larger size; 2d, by the antennae of the 9 

 being 14-jointed. If extended backwards, they would almost reach the 

 tip of the second abdominal segment; the joints three and four are of 

 nearly equal length, linear (that is, their length being out of all pro- 

 portion to their breadth) ; joint four is a little shorter than three, and 

 the following gradually diminish in length till the thirteenth joint, 

 the length of which is about double its breadth; the fourteenth is about 

 once and a half the length of the preceding; the antennae of S. ligni- 

 cola are shorter, that is, if extended backwards, they would hardly 

 reach the middle of the second abdominal segment; the fourth joint is 

 slightly more than half the length of the third, not linear, its length 

 being a little more than twice its breadth; the breadth of the eleventh 

 and twelfth segments is but little more than their length ; the thir- 

 teenth, or last joint, is about twice as long as the twelfth. As to the 

 male sex, the proportional length of the third and fourth joints of S. 

 lignicola %> is the same as in the 9 j that is, the third is almost twice 



