GOO Mr, D. Sharp and Mr. F. Muir on the Comparative 



base on dorsal and ventral side. Basal-piece slightly shorter than 

 lateral lobes. 



The specimen at our disposal is greatly destroyed by Antlwenus. 

 The elongation of the lateral lobes is remarkable. Burnieister 

 considered this form to be related to Enehirus, and there appears to 

 be a great similarity in the aedeagus of the two, but we cannot say 

 to what extent this is true of anything but the hard sclerites. The 

 general shape of the aedeagus is one that is frequent in the Melolon- 

 thine series of genera. 



Obs. — The aedeagus of Scarabaeidae is readily recog- 

 nised (if Trogidae, Lucanidae and Passalidae are excluded) 

 by the following definitions : — 



Tegmen greatly developed, the basal-piece enormous, 

 consisting of an anterior part unchitinised beneath, and a 

 more distal tubular part to which are attached apically 

 the varied lateral lobes (frequently called forceps or para- 

 meres) ; the median lobe drawu within the basal-piece, 

 and thus concealed, membranous except at the extreme 

 base where there are, more or less well developed, elastic 

 chitinous supports ; sac large, frequently provided with 

 remarkable, varied chitinous structures. 



The perfection attained varies greatly. There are 

 higher and lower forms in each of the great divisions. 

 The number of forms examined is not sufficient to enable 

 us to follow up this remark profitably. 



MORPHOLOGY, 



B. General. 



A BRIEF statement of the anatomical terms we have 

 used will be found in the early portion of the Memoir 

 (Orismology, p. 481). The term genital tube is used 

 because it conveys the idea of the chief characteristic of 

 the parts. Whatever else they may be, however different 

 they may appear, their combination to form a perfect 

 tube without orifices, is remarkable : the one " orifice " 

 that exists is not a real one. It arises from the invagina- 

 tion of the tube into itself. The genital tube is therefore 

 a doubled tube, one end of which is a continuation of the 

 body wall, while the other divides into a fork, of which one 



