4770 Insects. 



Hydroporus unistriatus. I have seen but one example, taken many 

 years ago in a chalk-pit, on the Madingley road, near Cambridge. 

 Stephens gives London and Devonshire as its localities : it is generally 

 distributed throughout the continent. 



Hydaticus stagnalis. Not common ; although occurring throughout 

 the Continent. I shall be glad to hear of any modern localities in 

 Britain (Steph. Illust. ii. 86). 



Agabus serricornis. By Mr. Hope, " at Netley, rare." There is no 

 reason why this insect may not occur in Soctland or the Orkneys, as 

 plentifully as in the north of Europe, Sweden and Lapland. 



Cybister Roeselii. This beautiful species is found in most countries 

 of Europe, though the single recorded instance of its capture in 

 England is in ' Stephens Illustrations,' at Walton, Essex, at the end 

 , of September, 1826. 



I feel that I need not apologise for sending you this list: it 

 appears to me not only to suggest practical matter for investigation to 

 the working entomologist, but to be of some little interest by pointing 

 out how far the labours of the present generation of Coleopterists have 

 been surpassed by those of the former : in this group at least we are 

 obliged to confess to the probability that our known Fauna of good 

 species is not so extensive as in 1830. I fear that among the 

 Helophoridse and Hydrophilidse, when they are properly understood, 

 our position will be found to be even more unsatisfactory. 



Might I venture to invite especially the attention of our Scotch 

 entomologists, and of naturalists who are proposing tours into the 

 Highlands, to the subject of this paper ? I am confident that any one 

 who will carefully examine the water-beetles of those districts will be 

 amply rewarded by the discovery of new species. During a visit of 

 only a few days in the autumn of last year, 1 was fortunate in taking, 

 inter alia rarissima, a new Hydroporus at Oban, and a new Dytiscus 

 in Mull ; both species (as are some six others, at present unknown to 

 us), common in Lapland. I shall be happy to supply exact details 

 and directions to any one who wishes to examine these localities, or 

 to any one who may propose to search the waters of his neighbour- 

 hood any information in my power. It is only by the united labours 

 of many that success in the investigation of any department of insect 

 life can be. attained ; but especially in this case, when, as in these 

 groups, peculiar habits forbid general distribution, and the lives of 

 generations of a species are confined to the limits of one solitary lake 

 or moor. This stimulates the efforts of the individual lover of Nature, 

 for by his researches he can enrich others, and this rewards combina- 



