VII POWER OF SMELL IN MOLLUSCA 1 93 



medusae which are stranded on the sandy bays near the Cape 

 of Good Hope. Dr. J. G. Jeffreys says ^ that quantities of the 

 common Neptunea antiqua " are procured on the Cheshire coast 

 by the fishermen placing a dead dog on the sands at low-water 

 mark during spring tides. The bait is then completely covered 

 with stones, which are piled up like a cairn. On the next turn 

 of the tide the heap of stones is visited, and the whelks are 

 found on the surface in great numbers, having been apparently 

 attracted by the smell of the bait, but unable to get at it." 

 Mr. W. A. Lloyd kept specimens of Nassa reticulata in a tank 

 in the sand, at the bottom of which they usually remained 

 buried. If a piece of meat of any kind were drawn over the 

 sand, the Nassa would appear above the surface in a few min- 

 utes. Half-picked beef or mutton bones, if placed in the tank, 

 were covered in a few minutes. In fact, no animal matter, 

 whether living or dead, could be introduced without the Nassa 

 smelling it, and coming up to see what they could get.^ 



Any one can experiment for themselves on the olfactory 

 powers of our common snails or slugs. Moquin-Tandon records^ 

 two interesting cases, one communicated to him by letter, the 

 other occurring to himself. His correspondent, a M. Parenteau, 

 was one day walking along a dusty high-road, when he noticed, 

 near the middle of the road, an empty bean-pod and two Arions 

 eating it. Attributing the meeting of feeders and food to mere 

 chance, he was walking on, when he noticed a second bean-pod, 

 and, about two yards away from it, a third Arion, hurrying 

 straight towards it. When the Avion had yet more than a yard 

 to traverse, M. Parenteau picked up the bean and put it in his 

 pocket. The Avion stopped, raised its head, and turned in 

 every direction, waving its tentacles, but without advancing. 

 M. Parenteau then carried the bean to the other side of the 

 road, and put it in a small hole behind a piece of stone. The 

 Avion, after a moment's indecision, started off straight for the 

 bean. Again the position of the precious morsel was changed, 

 and again the Avion made for it, this time without being further 

 tantalised. M. Moquin-Tandon noticed, one rainy day in the 

 botanical gardens at Toulouse, two Limax maximus approaching 

 a rotten apple from different directions. He changed the posi- 



1 British Conchology, i. p. xxviii. 

 2 Science Gossip, 1865, p. 259. ^ Mollusques de France, i. p. 130. 



VOL. Ill o 



