50 



INTRODUCTION. 



(or Pelobiidje), GyrtntdjE, and in more recent: years the com- 

 paratively newly discovered Amphizoid^e. To these have been 

 added the Cupedtdje, RnYSODiDiE, and Paessidje, in great measure 

 on account of the venation of the wings. Sharp, as will be seen 

 above, excludes from the series the three last mentioned families 

 and also the Gyrentdje, although he says that the Paussid.e and 

 Rhysodid^e will probably have to be included.* 



With regard to the Gyrinid^e, Sharp writes as follows (Cam- 

 bridge Natural History, vi, p. 216): — "The G-yrxnid^; are one 

 of the most distinct of ail the families of Coleoptera : by some 

 they are associated with the Adephagous series ; but they have 

 little or no affinity with the other members thereof. "Without them 

 the Adephaga form a natural series of evidently allied families, and 

 we consider it a mistake to force the Gyri:nid./E therein because 

 an objection is felt by many taxonomists to the maintenance of 

 isolated families. Surely if there are in nature some families allied 

 and others isolated, it is better for us to recognise the fact, though 

 it makes our classifications look less neat and precise, and increases 

 the difficulty of constructing tables." These remarks may well be 

 commended to the notice of systematists in cases in which families 

 have been ruthlessly crammed into abnormal positions for the sake 

 of uniformity. At the same time, the wings of the Gyrhstid^e are 

 distinctly adephagid in their venation, and unless they are raised 

 into a sub-order having equivalent value with the Adephaga, it is 

 best to retain them in their present position. I have already 

 pointed out (Coleoptera of the British Islands, i, pp. 209-211) 

 that the Gyrintd.e, if separated from the Adephaga, must be 

 regarded as finding in them their nearest allies, and have discussed 

 at some length their peculiarities and affinities. I did not, however, 

 take the wing venation into account, as very little attention had 

 then been paid to this point, so far as the Coleoptera were con- 

 cerned. In some points they approach nearer to the Hydrophilid,e 

 than to the Adephaga. 



In the arrangement here adopted the Cictndelidje, Carabid^e, 

 Haliplid.e, Dytiscid.e, Hygrobiid^;, Amphizoidje, Patjssid-E 

 and Ehysodid.e are regarded as Adephaga proper : the GyrinidvE 

 as doubtful, but as probably a separate offshoot from the stem of 

 the series : and the CupedidvE as outside this and all other series, 

 but as best placed near the Adephaga in the present state of our 

 knowledge. 



If for the sake of showing things more clearly we may, for the 

 moment, adopt the term " Protadephaga," used by Ganglbauer and 

 others, we might represent the group as follows : — 



* Dr. Sharp has since come to the conclusion that the Riiysodid.e are purely 

 Ca rabid and that Oiipes is very extraordinary and quite isolated. 



