1890.] 101 



9. The wliole arrangement of colour and disposition of markings tend to pro- 

 duce an exactly opposite effect in the appearances of the two insects. In crattegella 

 there is a constant tendency towards the comparative paleness of the medial area 

 being rendered strikingly conspicuous by the darker colouring of the basal area and 

 Bubterminal band ; whereas, in mercurella, the strong tendency is towards the 

 darkness of the medial area being brought into prominence by the relatively lighter 

 colouring of the areas on either side of it. 



I have but little doubt that the larva of cratcpf/eUa would afford 

 additioual points of contrast to that of the nearly-allied mercurella, 

 and I would, in conclusion, earnestly beg some kind friend, living in a 

 locality where the former is plentiful, to give us his assistance in the 

 matter by forwarding living larvae to Mr. G. T. Porritt, of H udders- 

 field, to be compared side by side with those of the latter. 



The Rectory, Corfe Castle : 

 March hth, 1890. 



A NEW BRITISH BEE— Pi? OSOP/S GENALIS, THOMS. 

 BY EDWABD SAUNDERS, E.L.S. 



I am glad to be able to add this species to our list, although it is 

 80 closely allied to confusa, Nyl., that it requires very careful exami- 

 nation to distinguish it from that insect. My attention was called to 

 it by Mous. Dachal, of Argentat, who sent me specimens of genalis, 

 Thoms., from his locality, pointing out how closely allied it was to 

 confusa, Nyl. I accordingly examined my specimens carefully, and 

 found 1 (^ and 2 $ of genalis, Thoms., taken at St. Leonard's, all in 

 the same locality. I have little doubt that it is mixed in other col- 

 lections with true confusa, Nyl. The following differences will serve 

 to distinguish the species : — 



Peosopis genalis. Thorns., Hymn. Scand., ii, p. 121. 



= Hyloeus confusus, Poerst., Verb, zool.-bot. Wien, 1871, p. 95 

 (^iiec Nylander). 



Differs from confusus, Nyl., in having the face rather longer, the 

 cheeks between the eyes and mandibles distinctly so ; the ,^ has also 

 the labrum white, whereas it is black in confusus, and the segments of 

 the abdomen beneath simple, whereas in confusus the 3rd segment has 

 a distinct central callosity, the apex of the 6th segment beneath is also 

 more truncate than in confusus. In the 7th and 8th segments the 

 characters are not very pronounced, but the transverse basal portion 

 of the 7th is narrower, and the hairs on the apical portion longer and 

 apparently more numerous. The apex of the 8th is more widely trun- 



