no THE DISPERSAL OF SHELLS. 



placed in empty drawers of my insect cabinet, since 

 which, up to the present time (October 19th, 1850), 

 they had never been opened, or if opened, the speci- 

 mens had certainly never been taken out. I concluded 

 of course that they were dead long ago, thinking it 

 more than probable that they never survived the 

 voyage to England, and therefore, a fortiori^ that two 

 years and a half in dry pill-boxes was quite sufficient 

 to remove all traces of existence. However, by immer- 

 sion in cold water, I find that many of them are 

 still alive ; and though a large proportion have 

 perished in this long interval, yet I have fourteen 

 specimens now before me crawling about with the 

 greatest activity. Thirteen of these are of the same 

 species, viz. : Helix {Carocolla) papilio, Lowe, and the 

 other Helix tectiformis^ Lowe, both collected May ist, 

 1848, on the Ilheo de Baixo, a small limestone island 

 off the south-western extremity of Porto Santo. ... I 

 may also mention that I possess a whole bagful of the 

 beautiful little Helix turriaila, Lowe, collected on the 

 Ilheo de Cima (another and smaller rock, off Porto 

 Santo), on the 24th of April, 1849, all of which, I find 

 by immersion, are alive, though the dry and dusty bag 

 in which they have been enclosed has never been opened 

 since they were placed there, exactly a year and a half 

 ago. The same may be said of Helix duplicata 

 [= H. bicarinatay Sow.] dind pazipercula^ of Lowe, (col- 

 lected at the same time as the last) ; I have both in 

 large quantities, perfectly active, though only now for 

 the first time taken out of the boxes in which they were 



