62 THE DISPERSAL OF SHELLS. 



now to be seen in the Manchester Museum, where it 

 was deposited by Mr. Hardy. This occurrence, however, 

 is not of much importance for us, for I am not aware that 

 dragon-fly larvae ever journey overland. 



The clinging- of bivalves to flying water- bugs and 

 -beetles is of more interest. Five individuals, at least, of 

 the water-scorpion [Nepa), a large flying bug, have been 

 caught with shells attached. A specimen with a small 

 Sphceriiun corneum on one of its legs, obtained in 1879 

 from Mere Mere, Cheshire, by Mr. J. Walken, is now 

 exhibited in the Manchester Museum, where, also, is 

 another specimen (preserv^ed in spirit) having attached 

 to it a much larger shell of the same species ; two others, 

 collected by Mr. Hardy in 1889, each carrying a shell 

 of Pisidium fontinale upon a leg of the hind pair, are. 

 also possessed by the Museum. (Fig. 2.) A fifth 



Pisidium fontinale upon the leg of a water-scorpion {Nepd) ; now in the Manchester 

 Museum. 



instance has been observed by Mr. Standen, who caught 

 a specimen with P. fontinale attached, in a pond near 

 Birch Hall, Manchester, on i6th May, 1890. 



A number of water-bugs {Notonecta) with '' small 



