SAMOUELLE'S 



The females of this and of the other species of the 

 genus have four wide and deep sulci or channels on 

 each elytra, closely covered with long and very coarse 

 hair. 



We are indebted to Charles Lyall, esq. jun. for this 

 interesting species, who has taken it in Kinnordy 

 Park, Scotland : in the British Museum is a speci- 

 men taken many years since, we believe in the Isle of 

 Arran, by our much-respected friend, Dr. William 

 Elford Leach. 



Mr. Kirby, in speaking of the means of defence of 

 insects, observes, " Willoughby has remarked a 

 curious circumstance with respect to a water-beetle. 

 (Dytiscus cinereus. Marsh) which ought not to be 

 overlooked. A transverse line of a pale colour is 

 observable upon the elytra of the male ; where this 

 line terminates, certain oblong pores are visible, 

 from which he affirms he has often seen a milky 

 fluid exuding." We have searched in vain for these 

 pores on the elytra with the deepest powers of our 

 microscope, and must observe, that most of the 

 Dyticide gives out this fluid ; but, from what we 

 have observed, generally from the incisions at the 

 head and thorax. We have taken the A. cinerus 

 in most of the ponds round London at all seasons 

 of the year. 



