Insecta. 25 



Uterus while it (the sac) is distended. A summary is given as to what is known 

 of the methods by which the end of the 5 tube or abdomen is held during copu- 

 lation by the c? tube or end of the cT abdomen; and it is mentioned that during 

 copulation the aedeagus is sometimes twisted through nearly a complete half 

 turn (p. 612). 



Taxonomy and Phylogeny. It is impossible to enter fully here into this 

 section, which is drawn up, as stated in the Introduction (p. 479) "to display the 

 part that a knowledge of the fertilising structures should have in tliese two de- 

 partraents of Coleopterology". The authors consider that the results obtainable 

 in taxonomy and phylogeny from a study of the c? genital tube will prove to be 

 of great importance when combined with results derived from other li- 

 nes of study. Althougb changes in Classification will be necessary, their Im- 

 pression is that most families now recognised will have their validity substan- 

 tiated by continued study of the d* genitalia. 



The authors again emphasise the fact that they have studied only the c? 

 part of the genital conduit; and that a study of the 5 portion, which would al- 

 most certainly reveal important structural differences is greatly needed from the 

 taxonomical and phylogenetic as well as from other points of view. 



Looking at Coleoptera from the point of view of the form of the c? genital 

 tube, 8 series of families are provisionally adopted: (I) Byrrhoidea, (II) Cu- 

 cujoidea, (III) Phy tophagoidea, (IV) Caraboidea or Adephaga, (V) Ma- 

 lacodermoidea, (VI) Tenebrionoidea, (VII) Staphylinoidea or Brache- 

 lytra, (VIII) Scarabaeoidea. The relationships of the families in each series 

 are shown by means of tables. The unsatisfactory series "Heteromera" is broken 

 up: Tenebrionidae and certain other families of it remain together in the series 

 Tenebrionoidea: the other families are placed in the series Cucujoidea. No dif- 

 ference has been found sufficient to separate Rhynchophora from Phytophaga, and 

 both are included in the series Phytophagoidea, which is tentatively derived from 

 a primitive Cucujid form. Caraboidea is taxonomically the simplest series. The 

 idea that the Scarabaeoid series is one of the most distinct is confirmed, though 

 the relationships of its families int er se present considerable difficulties, which 

 may render necessary an increase in the number of families. Certain families are 

 omitted for the present, owing to their c? apparatus not yet being understood 

 (Discolomidae, Cyphonidae, Trichopterygidae). 



In the phylogeny, palaeontology (which should be of the first importance) 

 throws no light at all on the present inquiry. The authors consider the simple 

 trilobe form of aedeagus, as present in Byrrhoidea, the simplest and most pri- 

 mitive of existing forms: but the families included in Byrrhoidea do not form at 

 all a homogenous series in other ways. Caraboidea, the most homogeneous series 

 as regards the form of the aedeagus, may possibly be derived from Byrrhoidea: 

 and the very distinct Scarabaeoidea seem to be linked by certain forms to Byr- 

 rhoidea. No very definite statement can be made as to the probable origin of 

 Cucujoidea, Staphylinoidea, Malacodermoidea, or Tenebrionoidea. Under the hea- 

 ding "Phytophagoidea" (pag. 634 — 639) the whole question of the nature of the 

 lateral lobes is discussed. They are present in various forms in Byrrhoidea, Ca- 

 raboidea, Tenebrionoidea, Staphylinoidea, and Scarabaeoidea. If certain struc- 

 tures are correctly homologised as lateral lobes, they are present also in Cucu- 

 joidea, which in that case may perhaps be derived from Byrrhoidea: but the 

 homology is not certain. It is still more doubtful whether lateral lobes are present 

 in the Rhyncophoro-Phytophagous series: if they are absent, then this series 

 differs in this respect from all the others, and can only be derived from an un- 



