Anatomy of the Male Genital Tube in Coleoptera. 615 
lobes. This coadaptation is carried to a most beautiful 
extent in Huchroma, but it is imperfect in some of the 
other forms, and, on the other hand, an imperfect condition 
of a similar kind obtains in Rhipiceridae. 
The Byrrhidae are treated as on the whole the most 
central of the families. It is to be understood that the 
relations between the Byrrhoidea and some of the other 
series are very close, and that with greater knowledge 
some of the families will be found to be misplaced. 
aHORE GEORYSSIDAE 
DASGI CYPHONIDAE) GYRI NIDAE 
ECTREPHIDAE HYDROPHILIDAE 
PTINIDAE CUPEDIDAE 
DERMESTIDAE OMMADIDAE 
PARNIDAE 
DERODONTIDAE THROSCIDAE 
MYCETOPHAGIDAE __— ELATERIDAE 
ADIMERIDAE neko ete RHIPICERIDAE 
COLYDIIDAE EUCNEMIDAE 
ENARSUS GROUP BUPRESTIDAE 
0 hGH ohh: SYNTELIDAE 
SPHERITIDAE 
ATRACTOCERUS NIPONIIDAE 
HISTERIDAE 
AFFINITIES OF THE BYRRHOID FAMILIES. 
It will be noticed that we have placed Cupes and 
Omma in this division as separate families; they show no 
approximation to the Adephaga, nor are they at all closely 
allied inter se. Although Omma is clearly a “ trilobe- 
form,” it is not the simplest condition thereof; the adapta- 
tion of the inner sides of the lateral lobes to fit round the 
median lobe, and the presence of a distinctly enlarged 
internal sac (although destitute of armature) indicate in 
fact a fair amount of specialisation. 
Cupes clathratus has a highly complex and_ peculiar 
organ, which, however, is of the trilobe form. It is also 
very remarkable by the structure of the last tergite and 
certain subanal appendages, but the consideration of the 
