NEWMAN ON TENTHREDININA. 261 



Genus. — Crcesus, Leach. 

 I have received specimens of a Croesus from Ireland, with 

 the body entirely black, with the MS. name Croesus Stephensii. 

 Mr. Stephens mentions this as a variety, saying it is probably 

 referrible to a distinct species. I could wish that so fine an 

 insect, with Mr. Stephens's name attached to it, may prove 

 distinct. 



Genus. — Fenusa, Leach. 



The two insects which I am about to describe as be- 

 longing to the genus Fenusa, differ extremely in general 

 appearance from the insects ordinarily described as consti- 

 tuting the genus ; nevertheless, in the neuration of the upper 

 wings, and in the number and relative proportion of the joints 

 of the antennae, there exists no observable difference ; and as 

 the genera of the family seem founded on these characters, I 

 shall not venture to propose new ones. 



Sp. 1. Fen. Ianthe. Nigra later ibus flaneolis : proalw fumosm 

 costa flaveola : pedes pallidi, femoribus omnibus plaga magna 

 nigra. 



This insect has a very large head, considerably wider than any part 

 of the body: the mouth, and a wide band round the eyes, are 

 yellow : the face, antennae, and crown of the head, black : the 

 body is black above and beneath, but the sides are pale yellow : 

 this colour forms a broad lateral line from end to end, in which 

 line the wings are situated : the forewings have the costal por- 

 tion tinted with the most delicate straw-colour, the remaining part 

 clouded ; the two marginal cells are of nearly equal size ; the 

 first submarginal cell is elongate, the second of moderate size : the 

 hind wings are transparent and uncoloured ; legs delicately straw- 

 coloured, with a black patch on the femora : size rather less than 

 that of Cladius difformis. 



This insect appears generally distributed ; it occurs in 

 the woods of the metropolitan district in May and June. 



Sp. 2. Fen. parviceps. Nigra, pedibus albidi, 



nigris ; alis amplissimis tiigro nebulatis ; caput {pro genere) 



This insect has a very small head : the face, region of the insertion 

 of the antennae extending upwards in two lobes, and margin of 

 NO. III. VOL. IV. M M 



