T. 1). A. and W . r. Cockciell un Bees. 47 



this group ; Imt wo liiul tlicse unsatisfactory on account of 

 tlio stress laid upon minor diircrcnccs of venation, while 

 certain radical differences in the mouth-parts of the genera 

 are overlooked. This defect was perhaps unavoidable in a 

 syno|)sifl of the genera of the whole world, many of which 

 could not at the time bo examined for mouth-characters ; but 

 it may be useiul here to indicate the lines on whicii a better 

 classilieation may be framed. 



Tribes. 



raraglos^oj very long, hairy Eucerini {Eucera;, Patton, Bull. 



U.S. CJeol. Surv. v. 471). 

 Parajflossa) not or hardly exceeding tirst 



joint of hibial palpi inthophnrini{Ant/ioj}hor(e,Fa,t- 



ton, torn. cit. 47'')). 

 I'ara^'losstevery sliort; form robust, hind 

 legs of 2 with ft copious .soopa: 

 ni'Otropicnl typos Ceiiti 



(run. 



C E N T ]{ I N I. 



Maxillary pHl[ii 4-j(iiiitt.d Centris, Fabr. 



Maxillary palpi H-jointod ; partxglossie very short, 



broad, thin, scale-like 1. 



1. First throe joints of maxillary pnlpi twice as 

 thick as, or at least noticeably thicker than, 

 the last three ; joint 4 about aa long as 3 . . E.romalopsis, Spin. 

 All joints of maxillary palpi of about equal 

 thickness and slender ; joint 4 longer than "J ; 

 1 not over half length of 4 ; clypeus yellow 



in male Anf/iophorula, Ckll. 



( Diadasiella, Ash m . ) , 



We find al.so certain differences between species of these 

 genera, which may be found to indicate subgenera. 



Centris, 



Last joint of maxillary palpi short, not half 

 length of poiiultimato joint ; penulti- 

 mate (third) joint hss than hiilf length 

 (if second : flight slow C. pallida, Fox. 



Last joint of maxillary palpi longer, over 

 halilentrth of pi'nultiinalo joint ; penul- 

 timate two thirds length of second : 



night very rapid C. rhodopus, Ckll. ; C. Hoff- 



viamci/yia, Ckll. 



Tiie measurements of the last three joints of the ma.xillary 

 palpi here given are in /x : — 



C. pallida . . . (2) 480,(3) ISO, (i) {SL 

 C. rhodopus ... (2) 3(»(), (3) 23a, (4) 138. 



The C. pallida studied is a cotype kindly sent by Mr. Fox. 



