LIST OF IRISH TESTACEA. 



enables me to communicate the following ac- 

 count of them. 

 " The creature probably passes the greatest part 

 of life at the bottom of the sea, but rises 

 sometimes to the surface, and to do so, it is 

 obliged, piscium more, to distend an air-blad- 

 der, which, however, is formed only for the 

 present occasion, and made of tough viscid 

 slime, swelled into a vesicular transparent 

 mass, that sticks to the head of the animal, 

 at the opening of the shell. This raises and 

 sustains it while it pleases to continue on the 

 surface ; but when it wants to return, it 

 throws off its bladder, and sinks. I have 

 taken up many of these insects alive, with 

 the bladder yet affixed to the aperture of the 

 shell, and still preserve some with it on, in spi- 

 rits. I have also observed many of the ve- 

 sicula themselves swimming upon the surface 

 of the water about that place, which induced 

 me to think they were thrown off' as the crea- 

 ture retired. It is observable, that on touch.* 

 ing the body of this insect, it diffuses a beau- 

 tiful purple liquor, of which colour the shell 

 generally appears when fresh." — Brown's Ja- 

 maica, p. 400. 



21. vivipara. Donovan, Br. Sh. t. 87. — Montagu, Test. Br. 



p. 386. In a stream at Newton Ardes, coun- 

 ty of Down ; rare. 



22. Jiemoralis. Donovan, Brit. Sh. 1. 13. — Montagu, Test. Br. 



p. 41 1, 412. H. hortensis. Common on every 

 road side, and in all its varieties. 



23. hortensis. Montagu, Test. Br. p. 407. H. aspersa. — Do- 



novan, Br. Sh. t. 131. Common in every 

 hedge and garden. 



