Anatomy of the Male Genital Tube in Coleoptera. 629 



The sac in Scarabaeidae is usually largely developed in 

 size, and also in form, showing lobes, or numerous diver- 

 ticula {Hexodon), or even large peculiar sclerites {Spilota 

 regina, Newm.). 



(We have already alluded to the reduction of the 

 median lobe in Scarabaeidae, but may here say that in 

 our anatomical section we point out that no line of sharp 

 demarcation can be drawn between median lobe and 

 sac. The reduction of the median lobe in Scarabaeidae, 

 compensated for — so to speak — by the remarkable de- 

 velopments of the sac is a matter worthy of special 

 investigation.) 



After these remarks on the Scarabaeidae, if we turn to 

 the Lucanidae, we again find remarkable diversities, but 

 of a totally different kind. The median lobe is well 

 developed. In some cases there is a conspicuous fine 

 terminal tube called the flagellum ; this specialisation is 

 more correctly described as a part of the sac. The sac in 

 Lucanidae frequently is not invaginated, but is crumpled 

 up, and the " flagellum " is merely a prolongation of that 

 one of its lobes (or parts) on which the orifice of the 

 duct is situated. The flagellum is clearly not of great 

 morphological importance. 



The basal piece in Lucanidae is veiy varied as regards 

 size, being sometimes quite small (CeratognatJnis), in other 

 cases {Neolamprima) large and tubular, but we have not 

 found any case in which it really approximates in shape 

 to the " tambour " of the Scarabaeidae. 



The lateral lobes of the Lucanidae are always well 

 developed (though very slender in Aesalus), and they are 

 never conjoined (we have pointed out that they are 

 conjoined in three different ways in Scarabaeidae). 



The genus Ti-ox (s.l.) is usually placed in Scarabaeidae. 

 In the recent Catalogue of European Coleoptera it imme- 

 diately follows the Lucanidae. So far as regards the male 

 structures it is impossible to look on Trox as a Scarabaeid. 

 It might, on the ground of these structures, be placed in 

 the Lucanidae, but if other considerations demand its 

 separation therefrom, it must form a separate family, 

 equivalent in import to each of the two families men- 

 tioned. The relation of Cloeotus and Anaides with Trox 

 requires a careful examination. 



This family Trogidae is of the first importance. It 

 seems to offer the only inkling of a connection of the 



