Molluscan Neurobiology: Snails

Pictures of 3 common UK molluscs used in neurobiology:

Click the picture for a larger view:
Helix aspersa
Lymnaea stagnalis
Picture of the snail, Helix aspersa
Picture of the snail, Planorbis
Picture of the snail, Lymnaea stagnalis

You can see more views of Lymnaea stagnalis here, including a time-lapse video of one moving around its tank

Snail feeding

Snails feed by opening their mouths and protruding their radula. In the well-pigmented Planorbis you can see this very well - see the second picture below. This 2Mbyte video shows the mouth opening and closing during the first three bites made by a Lymnaea in response to sucrose being added to the bath.

 Animation of snail feeding movements

As these pictures were taken through the glass along which the snails were crawling, you can see that different parts of the foot contract as the snail locomotes forward.
Lymnaea is  a very good snail to work on because
  1. it has a simple pattern of feeding, with 3 movements (protraction of the radula, shown green in the diagram) rasping and swallowing
  2. this pattern persists in the isolated CNS, which survives well at room temperature for over 4 hours, in a simple saline
  3. it has much less connective tissue than other molluscs, and
  4. its brian is coloured red, making it easy to find. In fact, each neuron (nerve cell) is coloured a slightly different shade of orange

Read On: find out about snail brains...

Page edited by Chris Elliott, 06 Nov 2003