THE KNTOMOLOGIST. 269 



A species that cannot be confounded with any other, both 

 sexes being entirely of a metallic blue-green : it most closely 

 resembles H. geratus, but is a larger insect: sometimes 

 small examples of the male are found agreeing in size with 

 those of H. aeratus, but the colour will distinguish these. 



26. Halictus ^ratus. 



Melitta aerata, Kirhy^ Mon. Ap. Angl. ii. 58, male, female. 



Halictus ffiratus, Smith, Brit. Bees, p. 37. 



This very distinct species is supposed by Prof. Schenck 

 and by other continental entomologists to be identical with 

 H. leucopus : this is an error, and has probably arisen from 

 the fact of the females of the two species being so very 

 much alike : I will endeavour to point out the differences ; 

 the females of asratus, leucopus and Morio are very difficult 

 to separate without an intimate knowledge of them. The 

 female of H. aeratus may be known from that of H. Morio by 

 its always having a green tint more or less bright on the 

 abdomen, and its metathorax is sharply truncate ; that of H. 

 Morio is rounded, and its abdomen is black : the thorax of 

 H. aeratus is usually of an uniform green, having a brassy 

 tint ; that of H. Morio has the metathorax blue-black ; some 

 examples occur with the entire thorax blue-black. The 

 metathorax in H. aeratus is truncate ; in H. leucopus it is 

 rounded. 



The male of H. leucopus is distinguished by its pale yel- 

 low tarsi and base of the tibiae. 



27. Halictus Morio. 



Hylaeus Morio, Fahr. Sysl. Ent. ii. p. 306 ; Sijst. Piez. p. 



321, male ; Schenck, Bees Nassau, p. 271. 

 Melitta Morio, Kirhy, Mon. Ap. ii. 60, male, female ; 

 Smith, Brit. Bees, p. 38 ; Nyland. Apum Boreal, p. 

 204. 

 A most abundant little bee, appearing early in the spring, 

 and frequently found on the flowers of chickweed. Its para- 

 site is Nomada furva : I have frequently taken them entering 

 the same burrows : it is found in all parts of Europe ; 1 have 

 received it from Denmark and Sweden. 



