1885.] 75 



to represent, iu part at all events, the obsolete eleventh joint. Thom- 

 son says with regard to this (Skandinaviens Coleoptera, i, 6G) — 

 "^ntenncd clavd haud compressd, ad speciem 2-articulatd, arficulo ultimo 

 ovato.'' Dr. Horn (Classification of the Coleoptera of North America, 

 p. 149) says — "Antennae fe^i-jointed, club two-jointed ;" in this point, 

 however, he cannot be right, for the nine joints of the antennse before 

 the club are very plain. Since drawing up the table in vol. xxi, p. 56, 

 in which I said of the Bhizopliagina — "Antennse 11-jointed, club 2- 

 jointed, the 11th joint wholly or partially enclosed within the 10th," 

 I hiive soaked a specimen for a long time in caustic potash, and then 

 mounted it in Canada balsam ; the sutures of all the other joints came 

 out very plainly, but there is no real suture visible in the club, which 

 is evidently formed of a single joint, however far we may regard the 

 ridges as representing the obsolete eleventh joint of the antennae, and 

 the second of the club. 



Rhizophagus, Herhst. 

 The species of Rhizophagus in many instances bear a very close 

 resemblance to one another, and there is considerable difficulty in dis- 

 tinguishing them from descriptions ; there are seventeen species in 

 the European list, of which we possess ten ; they are found under 

 bark of decaying or dead trees at all times of the year, but especially 

 in the spring. 



I. Antennae with club truncate. 



R. cribratus, Gryll. — Dark rust-red, depressed ; thorax about as long as broad. 

 very strongly and coarsely punctured ; elytra rather widened in the middle, with 

 rows of strong punctures ; under-side of head and sides of body strongly punctured. 



Length, If lin. 



The truncate club of the antennse and sub-quadrate thorax at 

 once separate this very distinct species ; it is very local. Stretford, 

 Mr. Eeston ; on decayed roots of lime trees, Withington Common, 

 near Manchester, Mr. Chappell ; Weybridge, Esher, Eichmond Park, 

 New Forest, Eeigate, Tilgate Forest, Birch Wood ; Ireland (Galway), 

 Mr. J. J. Walker ; Studley Park, Eipon, in fungus, Mr. G. E. AYater- 

 house. 



II. Antennae with club rounded at apes. 



i. Colour testaceous or ferruginous, sometimes with indications of a darker 

 shade on disc of thorax and elytra. 

 1. Punctuation of thorax close and very fine. 

 R. depressus, Fabr.— Light rust-red, suture of elytra darker ; body depressed ; 

 head of male large, about as broad as thorax, of female narrower ; thorax longer 



G 2 



