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 very varied as regards 
size, being sometimes quite small (Ceratognathus), in other 
cases (Veolamprima) 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 7Z’ox (s.1.) 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 Z’rox 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 
