Anatomy of the Male Genital Tube in Coleoptera. 615 



lobes. This coadaptation is carried to a most beautiful 

 extent in Uuchroma, 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. 



DASCILLIDAE 



(EXCLUDING CYPHONIOAE) 



ECTREPHIDAE 

 PTINIDAE 

 DERM E5TI DAE 



DERODONTIDAE 

 MYCETOPHACIDAE 

 ADIMERIDAE 

 COLYDIIDAE 



ENARSU5 CROUP 



CEORYSSIDAE 

 CYRINIDAE 

 HYDROPHILIDAE 



CHELONARIiDAE 



ATRACT0CERU5 



CUPEDIDAE 



OMMADIDAE 



PARNIDAE 



THR05CIDAE 



ELATERIDAE 



RHIPICERIDAE 



EUCNEMIDAE 



BUPRE5TIDAE 



SYNTEUIDAE 

 SPHERITIDAE 

 NIPONIIDAE 

 HI5TERIDAE 



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 Adejjhaga, nor are they at all closely 

 allied inter se. Although Omnia 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 iu 

 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 



