222 Mr. J. Walton on the genera Oxystoma and Magdalis. 



Ulicis to the large females of Ap. atomarium, and the female of 

 Ap. Hooker i to that of Ap. Genista : in the construction of the 

 rostrum Ap. fuscirostris resembles Ap. Ervi, Viciae, vicinum and 

 vorax, whilst others are more curved and deflexed, as Ap. varipes, 

 Ononides of Gyll., &c. Many species both foreign and British 

 are clothed more or less with hairs or bristles, and some with 

 elongate scales of various forms, as Ap. Makes, vernale, fusciros- 

 tris, Ulicis and Genista, but these characters are only regarded 

 as specific, not generic. All the species of the genus Apion have 

 the rostrum with two oblique fossulets or oblong fovese more or 

 less deep, terminating outwardly at the sides and inwardly be- 

 neath the rostrum ; their external edges or margins are more or 

 less incrassated or dilated, and are placed at a greater or less 

 distance from the base; the antennae are inserted within the 

 fossulets at the under sides, and always in the same relative 

 situation ; the form of the rostrum, the structure of the antennae, 

 together with the sexual dissimilarities in those organs are so ex- 

 tremely anomalous and discrepant in this natural group of insects, 

 that it is very difficalt to find good or fixed characters for the 

 foundation of genera ; the species are held together by general 

 habit, and especially by a peculiarity in the form of the trochan- 

 ters first described by Kirby*. 



The three species comprised in the genus Oxystoma are fur- 

 nished with a remarkable process at the base of the rostrum be- 

 neath, which I shall endeavour to describe under their respective 

 names, and which, as far as I know, has not been noticed before ; 

 but these appendages or processes are not confined to those spe- 

 cies, for Apion Carduorum participates, and others in the genus 

 Apion have modifications of the same, but not so fully developed ; 

 Oxys. fuscirostris, Ulicis and Genista differ however from all the 

 species of the genus Apion that I have examined in not having 

 antennal grooves at the base of the rostrum beneath, or under the 

 head, as in Apion Cracca, Pomona and subulatum ; these charac- 

 ters may be considered of sufiicient importance to constitute a 

 new genus, and I therefore leave Oxystoma as it is. 



1. O. fuscirostris, Fab., Steph. 

 Apion melanopum. Marsh., Kirb. 

 — fuscirostris, Germ., Schonh. 



This insect is sparingly clothed with whitish and cinnamon- 

 coloured elongate scales, which are distinct and well-defined when 

 magnified. The rostrum is thickened at the base above, and 

 dilated on both sides at the points of insertion of the antennae, 

 and has two deep oblong foveae very near the base beneath, 



* Linn. Trans, vol. x. p. 347. 



