NO. 1361. REVISION OF AMEllIl AN SIPHON A PTERA—BA KER. 385 



Taschenbcrf*- used the liitor niiiuo aerratlirps^ of (i(M-Viiis. :iiid I at 

 lirst followed him in thi.s us in other inatter.s, thougli the (H-dinary 

 rules of zoological nomenelatiire do not permit of its use. 



I believed most heartily in Mr. Rothschild's much-needed setrreo-ji- 

 tion of the composite species avlurn^ but his similar attempt in the 

 case of ca7its and fells can not. it seems to me, possibly stand. He 

 himself says that any constant distinctive character is lackinj^- in the 

 females. The diU'ercnce in the males which he indicates would be \ er}' 

 slight at best; they relate principally to the mmiber and arrangement 

 of the ])ristles on the di.scs of the male claspers. In America this is 

 certainly widely variable. It can only ])e said that if his definition of 

 these two species must be accepted, then a number more should be 

 described from dogs and cats in this country, and, as in the first two, 

 so the females of all would be practically indistinguishable. 



CTENOCEPHALUS SIMPLEX Baker. 



This form, originally described as a variety of InaequaUs^ is a dis- 

 tinct species. It occurs on Lcpux in Michigan. 



CTENOCEPHALUS INi^QUALIS Baker. 



This was originally described from part of the material obtained b}" 

 Prof. A. B. Cordly on Lepua near the Grand Canyon, in Arizona. 

 Afterwards 1 collected the same thing on a Lepm at Arboles, Colo- 

 rado, and Professor Aldrich sent me specimens from Moscow, Idaho. 



Genus CERATOPH YLLUS Curtis. 



1882. Ceratop}ni/lut< Curtis, British Entoinol()<fy, IX, No. 147. 

 1898. ('mttophyllK.s Wagner, Hor* Soc. Ent. Ro.ss., XXXI, p. 557. 



This is the largest genus in the order, containing many nearly 

 related and very puzzling forms. Most of the species are very closely 

 confined to their especial hosts, and none are cosmopolitan. C. g<iJ- 

 lifice, or some of the European species affecting house rats or house 

 mice, would be the most lik(dy to become so. We have no ri'cord as 

 yet of the occurrence of any of these in America, though it is almost 

 impossible that they should not have ])een ])i-ought here. The fact is 

 that no systematic attempt has l)een made to collect them. This is 

 nuich to be regretted, and it is hoped that opportunity will soon 

 otler to supply the necessary data. 



In his very proper rehabilitation of this geiuis. Di-. Wagn(>r uses 

 the an-angement of the spines on the under side of tlu" tiftli tarsal 

 joint as a distincti\e character of special im])ortance. It has l)een 

 impossible for nu' to apply this to the many .Vmerican sj)eci«>s. As 

 defined by him, these spines in (Jei'atojtlnillns are (onlined to '1 rows 

 of 5 each on either margin, in Ctenophtliuhinis the first pair being 



