1891.] 289 



NOTES ON THE BRITISH SPECIES OF IIALTICA. 

 IJY JAMES EDWAUDS, F.E.S. 



Tlic following notes arc nothing more tlian tlie result of an 

 attempt to furnish an intelligible definition of the species of IlciJtica 

 known to inhabit Great Britain. The subject is for many reasons one 

 of more than ordinary difficulty, and I am bound to admit that my 

 success has been scarcely so complete as I could wish ; but as I have 

 been fortunate enough to enjoy special facilities for the investigation 

 of the matter, I think it well to publish a statement of the conclusions 

 at which I have arrived. 



A considerable quantity of material has been placed at my dis- 

 posal by Mr. Champion, Dr. 8harp, and others; and I am, in particular, 

 indebted to the Rev. Canon Fowler for the loan of the actual speci- 

 mens referred to in his "Col. Brit. Islands," with the labels of the 

 continental authorities still attached, and to Mr. P. B. Mason for the 

 loan of the E-ye and Wilkinson collections. 



The difficulties which attend any attempt at the effective definition 

 of the species of this genus have long been recognised, and are 

 chiefly owing to the fact that the points upon which we are accustomed 

 to rely for specific differences are subject to so much variation as to 

 be in most cases practically worthless as characters of limitation. 

 Fortunately, the form of the cedeagus affords constant structural 

 differences, and it seems to me that the character next in importance 

 in point of practical value is that of the general facies. It must 

 not, however, be assumed that I dismiss the various characters which 

 have been employed for the separation of species here (and which look 

 so well on paper) w^ithout sufficient reason ; on the contrary, I have 

 spared no pains in testing the utility of them all. The presence of 

 three or four teeth to the mandibles has been used to divide the 

 species into two groups, but the fact is that the mandibles are trifid 

 at the apex in all, the so-called fourth tooth being simply an angular 

 projection, of greater or less development, on the inner edge of the 

 upper-side of the mandible ; it is true that this projection is more 

 apparent in the smaller species, but the variation in its development 

 frequently leaves one in doubt whether the individual specimen under 

 examination should be regarded as having three teeth to its mandibles 

 or four. Another very variable character is the callosity at the an- 

 terior angles of the thorax ; it is present in all, but reaches its greatest 

 development in H. h/thri. Equally unsatisfactory are the characters 

 derived from the humeral callosity of the elytra, the frontal tubercles, 



