PHYTIVOROUS MOLLUSCA. 325 



The marine tribes live on sea-weed,- 



" part single, or with mate, 



Graze the sea-weed their pastures, and through groves 

 Of coral stray ; " 



and it is probable that the species in general are not limited 

 to any particular weed, nor are even very nice in their selec- 

 tion. At the same time it may be observed, that some are 

 rarely found except on one and the same plant, as, for 

 example, the pretty Patella pellucida, which pastures almost 

 uniformly on the broad frond of Laminaria digitata, and has 

 shown both sense and taste in choosing so wide and tender 

 a field. Still more provident in its way, is another com- 

 mon species of Patella, or, perhaps, a variety only of that 

 just mentioned, which is usually found occupying a cavity 

 or cell in the root of the same sea-weed. Insinuating itself 

 amid, or under the entangled root, it eats into its very core 

 until a cavity is made sufiiciently large, where it may find a 

 full repast ever at hand, and at the same time a snug resi- 

 dence, secure from almost any foe, and sheltered from every 

 ordinary storm. I have often admired the apparent sagacity 

 of the creature in its choice, and amid the bustle of life, 

 have sometimes envied its quiet seclusion, which is not so 

 strict as to exclude all society, for I have frequently seen 

 two Patellae dwelling together in the same " peaceful her- 

 mitage." 



The land tribes seem to refuse no tender herb : we know 

 that they will eat with avidity the spring corn, clover, peas, 

 and turnips ; they are very fond of all kinds of fruit ; and 

 the mushrooms afibrd the slugs a grateful delicacy, even the 

 poisonous, acrid, and milky species being greedily devoured 

 by them.* To me, they seem to prefer all these in a fresh 

 state ; my personal observation leads certainly to this con- 

 clusion, though I am aware it has been said that they, like 



Anim. iii. 72 and 86. — Adanson had given the distinguishing characters 

 between the zoophagous and phytophagous pectinibranchial niollusca very 

 correctly.— Hist. Nat. du Senegal, p. 80, 81, 193. The Phytophaga are 

 " eminently distinguished from the carnivorous race by two characters ; 

 their mouth does not form a proboscis : and the aperture of their shell is 

 entire, — in other words, without the notch or canal for the passage of the 

 siphon." — Swainson's Mulucology, p. 56 and 158. 



* See Ann. Nat. Hist. ix. 73, It is stated somewhere in the Gardener's 

 Magazine, that Helix aspersa has been seen to feed on the fiery-flavoured 

 foliage of the Clematis flammula! Of a very acrid agaric described by 

 Lister he says, "I observed these mushrooms even then, wlien they abounded 

 with milk (not to be endured upon our tongues), to be exceeding full of tlv- 

 maggots ; and the youngest and tendcrest of them were very much eaten 

 by the small, gray, naked snail." — Corresp. of liaj/, p. 100. 



