656 Proceedings of the Royal Irish Academy. 



[X atratus, Heer. The records Armagli ('88 J. 2), and Carling- 

 ford ('88 J. 1) are to be refen-ed to X imnctulatus, I*ayk.] 



X. tricolor, F. 



TJlSTEE. CoiSTfATJGHT. LeIXSTEE. MimSTEIt. 



Donegal, Down, Sligo, Galway, Louth, Dublin, Wicklow, Kerry. 



Mostly at seaside in decaying seaweeds, but also inland — not 

 common. 



X. cribripennis, Fauyel. 

 Ulstek. 



Donegal (Buncrana, '00 B; Bundoran and Coolmore sandhills^ 

 Eiver Erne bank near BaUyshannon, '94 J. Ht. Cr.). — Derry (Magil- 

 ligan sands, '00 B.). 



"We are indebted to M. Fauvel for the identification of this insect 

 — specimens of a XanthoUnus which had been representiag X distans 

 Kr., in our collections, have been refen-ed by him to the present 

 species. We cannot find any previous record of X. crilri])ennis^ and 

 have therefore the pleasiu'e of adding this species to the British list. 

 The following are the characters by which it may be distinguished 

 from X. distans, derived from Ganglbauer {ex Fauvel) : — 



Closely allied to X. distans, generally larger, with a pronounced bronze lustre, 

 head more closely punctured on the sides. Thorax -with the anterior angles more 

 strongly rounded, with from thirteen to fifteen punctures in each dorsal series, 

 those on the sides being twice as close, and very irregular. The elytra are longer, 

 and more finely and closely punctured than in X. distans. 



On comparing our series of the D'ish species which we had sup- 

 posed to be X distans with the specimens named by M. Fauvel, and 

 with types of the true X distans (fi'om Transsylvania), we fijid that 

 they are all to be referred to X. crihripennis, Fauvel. The above- 

 mentioned differences are very evident, except that the Irish specimens 

 are rather smaller (7-8 mm.) than X. distans, but this character is of 

 little value, within limits, as the species of XanthoUnus often differ 

 considerably in size : very possibly the Irish examples represent a 

 small-sized race of the species. The general colour also seems to be 

 lighter than in distans, especially that of the elytra, and the head and 

 thorax have a very noticeable gTeenish-bronze lustre, of which, in our 

 types of X. distans, there is scarcely a trace. The character of the 

 punctuation offers the best means for distinguishing X. crihripennis 

 from X distans, the difference being at once apparent when actual 

 types are compared. 



