185 



perliaps I should say of any) value must have regard to more 

 than local fauna, and can hardly be made profitably by any who 

 have not access to the vast collections that are stored in the great 

 museums of Europe. Recognising this fact I have adopted the 

 principle of referring the new species I have to describe to exist- 

 ing genera wherever it is at all possible to do so, adding as full 

 information as I can give of the characters that render their posi- 

 tion in those genera only provisional. I propose new generic 

 names only for insects which would be so out of place in known 

 genera that their location there would be likely to mislead. Ac- 

 cordingly it will be found that I have attributed by far the larger 

 number of the Coleoptera described to the genera Scymnus and 

 Rhizohius, although some, at least, of them can hardly be con- 

 sidered truly congeneric with European types. 



To Scymnus I have referred all the species before me present- 

 ing the following combination of characters : — Eyes neither 

 ■coarsely granulated nor oblique in position ; antennae short, of 

 not less than ten joints ;* epipleurse devoid of well-defined fovefe; 

 prosternum not provided with a prolongation covering the mouth 

 organs in repose, mesosternum not carinate longitudinally; 

 suture between the first and second ventral segments, obliterated 

 (or at least much enfeebled) in the middle; claws £^pendiculate ; 

 base of antennae exposed. 



All the species I have attributed to Scymnus correspond with 

 the above formula, with the exception of the last, which differs in 

 specified respects. Were it not for that species I might add to 

 the formula "abdominal lamellae incomplete." In some respects 

 (especially the structure of the prosternum) the insects thus as- 

 sociated difier much inter se, as I have indicated by dividing them 

 into subgeneric groups, to which, however, I have thought it better 

 not to appty names. 



The following I have treated as the essential characters of 

 Rhizohius : — Eyes coarsely granulated and oblique in position ; 

 antennae more or less long, of eleven joints ; epipleurae devoid of 

 well-defined foveas ; prosternum not with a prolongation covering 

 the mouth organs in repose ; mesosternum not carinate longi- 

 tudinally ; suture between the first and second ventral segments, 

 not noticeably enfeebled in the middle; claws appendiculate ; 

 base of antennae exposed ; tibiae more or less slender. 



The species in my hands presenting the above characters differ 

 considerably in some respects inter se, enabling me to group them 

 in sections that (unless intermediate forms be subsequently found) 

 would seem to be of generic value. 



* I believe that in all cases they consist of eleven joints ; in the case of several 

 species, however, I have been unable to satisfy myself absolutely on the point. 



