166 Mr. E. Saunders' Synopsis of 



end of the Andrenidcs, show a decrease in the numbers, 

 of twelve, since 1876, the date of publication of the 2nd 

 edition of his British Museum Catalogue of British 

 Hymenoptera. 



The increase of three in the Diploptera is caused by 

 the discovery of that number of additional species to 

 our list. The decrease of twelve in the Anthophila is 

 accounted for thus : eleven new species have been added 

 to the list, and twenty-three of those given by F. Smith 

 have been rejected for the following reasons : three as 

 being of doubtful British origin, viz., Prosopis variegata, 

 P. bifasciata, and Halictas interritptus ; five as being 

 stylopised forms of well known species of Andrena ; three 

 as being autumn broods of species which also occur in 

 the spring ; two as being males of already described 

 females, and which had not before been properly mated ; 

 and the remaining ten as being mere forms or races 

 which I have not thought important enough to retain as 

 distinct species. 



My thanks are due to a great many who have helped 

 me very much in the loan of specimens, and in other 

 ways ; and I have especially to thank Professor Perez, of 

 Bordeaux, and Mr. C. Eitsema, of Leyden, for much 

 valuable assistance that they have given me in comparing 

 our British specimens with those in their collections. I 

 must also thank the Eev. E. N. Bloomfield and Eev. W. 

 Farren White ; also Messrs. Billups, Bridgman, E. P. 

 and F. Collett, C. W. Dale, E. Parfitt, V. Perkins, and 

 E. Service for many specimens which they have given 

 me, and for valuable communications as to localities, &c. 



HYMENOFTEBA. 

 ACULEATA. 



Hairs simple, or in some cases twisted, but not branched or 



plumose .. .. .. .. .. .. .. Section 1. 



Hairs more or less branched or plumose, at least those on 



the thorax . . . . . . . . . . . . . . Section '2. 



Section I. 



1. Wings not folded longitudinally . . Heterogyna — Fo^mre 



2. Wings (at rest) folded longitudinally . . . . . . Diploptera. 



