310 ENEMIES OF MOLLUSCA. 



Cuttle-Fish and Loligo, eject, as is well known, a coloured 

 fluid, and so escape in the midst of the clouded water 

 they have produced. The lanthina and Aplysice have the 

 same powers, especially the large Dolabella Rumphii; and 

 the Actinia squirt water in the face of the intruder, as 

 they shrink back into their burrows. 



When we consider how very numerous the enemies of 

 Molluscous animals are, we must allow they have much 

 need for such ingenious modes of defence. On the high 

 seas they constitute the prey of Dolphins, Cachelots, and 

 of a thousand voracious fishes, besides insatiate Alba- 

 trosses and industrious Petrels, which are ever on the alert 

 to capture them. Along the shores they are snapped up 

 by patient Turnstones, and enterprising Oyster-catchers ; 

 and in fresh-water ponds they become the lawful prey 

 of Plovers, and all those other birds that love oozy 

 watery haunts. Terrestrial Mollusca find enemies, even 

 among insects, many Silpkida attacking and destroying 

 them in the same manner as the Hydropliili and other 

 Philhydrida prey upon and devour the Pahdinas and 

 Lymnteas, among aquatic genera. 



The list of genera of fresh-water shells in these islands 

 is limited, as far as my experience goes, to Paludina, 

 Lymnaa, and Assimincea ; no Succinece, Neritinae, Pla- 

 norbes, Ampullarite or Melanits were observed by us. 

 The land-shells were Helix, Pupa, Clausilia, Truncatella, 

 Carocotta, and Cydostoma. 



In the shallow pools left by the receding tide on the 

 shore of Koo-kien-san, one of these islands, I discovered 

 a large species of Dorididce, which appears to be the type 

 of a new genus, differing from all the other genera of the 



