THK ENTOMOLOGIST. 255 



been broken and swept away. The columnar structure is 

 distinctly seen : its sides and some of the columns, which 

 are generally five or six-sided prisms, appear to be 200 feet 

 in height. 



This remarkable volcanic region was first noticed in 1855, 

 by Mr. Frederick Foot, of the Geological Survey, and, not 

 having yet got into the guide-books, is scarcely known, and 

 more rarely visited than it deserves to be, for it needs not to 

 be a geologist to appreciate the grandeur of these basaltic 

 cliffs, or the beauty of the wild glens amidst which they 

 are placed. 



Volcanoes and ice seem strangely out of accord with the 

 present aspect of Killarney, shrouded in evergreen woods of 

 almost tropical luxuriance ; but there is no doubt those 

 mighty agents, frost and fire, have aided to produce the 

 present beautifully varied outline, upon which the eye never 

 tires of resting, and it may even be that the rude forefathers 

 of our race saw it in the icy dress which is now difficult, 

 even in imagination, to restore. 



Edwin Birchall. 



Bradford, Feb. 1, 1867. 



A Revision of ihe British Species of the Genus Bombas. 

 By Fkedeeick Smith, Esq. 



(Continued from p. 243). 



The nests of the surface-building Borabi may be taken 

 without any chance of their making a formidable resistance ; 

 the moment their dwelling is disturbed a sudden panic ap- 

 pears to render them incapable of defending their domicile : 

 this has been my experience as regards the dwellings of 

 Bombus senilis, B. Sylvarum, B. Derhamelliis, B. Pratorum 

 and B. fr a grans. 



The size of the nests, and consequently the number of 

 their inhabitants, depends, in the first instance, upon the 

 period of the season when it is discovered ; in early summer 

 the communities are small, but they increase as the season 

 advances. Mr. Shuckard says they have two broods during 

 the season : such a statement is directly opposed to my own 



