THEIR MODES OF DEFENCE. 309 



Muscles; the flesh, however, is red^and very bad-flavoured. 

 Some Monodonta, which I have eaten among the Korean 

 Islands, are quite peppery, and bite the tongue, pro- 

 ducing the same unpleasant effects upon that organ, as 

 the root of the Arum maculatum, or leaves of the Taro, 

 but in a much less intense degree ; and a species of My- 

 tilus, found in the same locality, has very similar unpa- 

 latable qualities. 



The Paludina, common in the Padi fields, in these 

 islands, escapes detection, by covering itself over with 

 small hard masses of mud, in which state it resembles 

 those turbinated habitacula of the larvae of some fresh- 

 water insect, to which Swainson has applied the name 

 Thelidomus, conceiving them to be true shells, repre- 

 senting, I believe, in his quinary system, the genus 

 Phorus. This peculiarity of the Paludinas did not 

 appear to me to be accidental, as I have seen shells of the 

 same genus in England, Java, and elsewhere, which entirely 

 wanted the very peculiar appearance above alluded to, and 

 the Lymneeas, in the same ponds, were not muddier than 

 is usual with those shells. All Mollusks have certain 

 means of avoiding threatened dangers. The Gasteropods 

 withdraw their bodies within their shells, 



As the snail, whose tender horns being hit, 

 Shrinks backward in his shelly cave with pain, 

 And there, all smother'd up, in shade doth sit, 

 Long after fearing to creep forth again. Shakspeare. 



The Pteropods contract their bodies when alarmed, and 

 sink suddenly to the bottom ; the Bivalves close their 

 shells, and bid defiance to the enemy ; the Pholas and 

 Solen, like many of the Cephalopods, including the 



