Rhizophagina.'] CLAVICORNIA. 263 



is finally done, but at present the tribe certainly does not agree with 

 the Nitidulidae by reason of the heteronierous tarsi of the male, nor 

 with the Trogositidse, because its members have the fourth tarsal joint 

 the smallest, whereas the Trogositidse have the first joint the 

 smallest ; the antennae also present a great point of difference, con- 

 sisting to all intents and purposes of ten joints, with a solid club ; after 

 careful examination of a specimen soaked for a long time in caustic potash 

 and mounted in Canada balsam, I cannot discover any real suture in 

 the club, and however far we may, like Erichson, Thomson, and others, 

 consider the ridges, which are apparent externally, as representing the 

 obsolete eleventh joint of the antenna?, yet the club is really 1-jointed 

 and solid ; besides the extensive genus Rliizophagus, only three or four 

 small exotic genera (Europs, Mimema, and Crine) are contained in 

 the tribe, but the number will in all probability be considerably 

 increased ; several forms yet remain to be worked out in the exten- 

 sive series of Mtidulidae collected by Mr. Champion in Central 

 America ; one or two of these allied genera have the club distinctly 

 2-jointed. 



RHIZOFHAGUS, Herbst. 



Upwards of forty species are comprised in this genus, which are 

 almost entirely confined to temperate and cold climates ; two or three 

 have been described from Tahiti, Cuba, Ceylon, &c. ; they are elongate, 

 more or less depressed insects, and are found under bark and at sap ; 

 there are sixteen European species, of which ten are found in Britain. 



The larva of M.' depressus is described and figured by Ferris, Ann. Fr., 1853, 

 p. 599, pi. 18, fig. 84 92 ; it is 6 mm. in length, rather depressed, and almost linear, 

 except that the head is narrower than'the prothorax ; the head and prothorax are reddish, 

 the base of the latter being whitish, and all the succeeding segments, except the last, 

 are reddish for their basal half, and whitish for their apical half; the head is long, 

 almost elliptical, with two long impressions ; the prothorax is much longer than tho 

 meso- or metathorax, and is rounded and narrowed in front ; the last segment is 

 entirely ferruginous, and is furnished on its upper surface with two distinct tubercles ; 

 this segment behind is divided into two lobes, each of which terminates in three 

 strong teeth j on the under-side is a small anal appendage, which is used, as in other 

 allied species, for progression ; this larva preys upon the larvae of Hylesinus, and 

 probably other wood-boring beetles. The larvae of many of the Nitidulidse and other 

 families which frequent trees ai'e of very great benefit to the forester; for, as 

 M. Ferris remarks, they are of great service in keeping within bounds the multiplica- 

 tion of some of the insects that are most destructive to various forest trees. 



The pupa of Rhizophagus depressus is rather long and narrow, of a white colour, 

 and furnished on vertex and at sides with long silky hairs ; it does not, however, present 

 any striking peculiarity. 



Other larva? of various species of Rttizophagus have been discovered, 

 but they do not differ much from the one first described, except as 

 regards the arrangement of the teeth at the end of the lobes of the 

 last abdominal segment. 



I. Antennas with club truncate ,. . . K. CEIBRATUS, O-yll. 



II. Antennaj with club rounded at apex. 



