34 ABIA NIGRICORNIS. 



lengths and thickness of the antennal joints vary, 

 especially in the club and in the length and thickness 

 of the fourth joint compared to the third. The colour 

 of the antennse in typical sericea varies, the base and 

 apex being not infrequently blackish. I can also dis- 

 tinguish variations in the sculpture of the abdomen in 

 specimens which have the typical sericea antennae. I 

 fancy that the distinctness of the joints of the club 

 depends on the development of the individual. Gene- 

 rally in candens the second abdominal segment wants 

 the central keel, but in some individuals it is indicated, 

 although not so strongly as in typical sericea. 



The two forms occur together in Scotland, and are 

 equally common. This fact would appear to militate 

 somewhat against the specific distinctness of candens 

 and sericea. Unfortunately I have not retained any of 

 the specimens bred from the Iarva3 I have described 

 and figured under sericea. I have also south of Eng- 

 land examples. I may add that I have Scotch speci- 

 mens which are in every respect identical with examples 

 named by Dr. Puton from the Yosges. 



Konow records candens from Switzerland and West- 

 phalia. 



3. ABIA NIGEICOENIS. 



Abia nigricornis, Leach, Z. M., iii, 113, 1; Curt., B. E., ii, 

 pL Ixxxix (1825); Zadd., Schr. Ges. 

 Konig., iii, 270. 



Cimbex senea, Klug, Berl. Mag., i, 91, 7. 



Abia (Cimbex) senea, Toll., Tijd. Ent., i, 144, pi. v; Zool ss 

 7523. 



bifida, Thorns., Hym. Sc., i, 28. 



lonicerse, Kirby, List of Hym., i, 14, 6. 



Antennae black; basal joint almost globular, transverse, thicker; 

 second narrower, shorter, distinctly transverse ; third slightly curved, 

 thickened at apex, four times longer than the two first ; fourth dilated 

 in the middle, shorter and thicker than preceding ; fifth shorter, con- 

 siderably thicker, and apparently biarticulate. Head small, densely 

 covered with a long, fuscous pubescence, much narrower than the 

 thorax, rounded in front, truncated behind; brassy. black; apex of 

 mandibles fuscous. Eyes widely separated, oblong-oval; labrum trans- 

 verse, pilose. Thorax obscure brassy-black, a little shining ; mesonotum 



