EXPEDITION TO A LAKE. 
207 
end, sounding as we went with a hand lead. We 
found the lake very shallow, having only twenty- 
one feet in the deepest part. The bottom, we 
observed, was composed of soft black mud, and, 
towards the shallow further extremity, of fine clean 
sand ; the circumference being bounded by a belt 
of shingle. The water was perfectly fresh, very 
clear, and extremely free from weeds. We noticed 
but few fish, and no trout or salmon. Several 
plaice and mullet were, however, caught in the 
narrow channel leading from the lake to the bay. 
* • 
The only crustacean visible was the “ hairy-handed 
crab,” Eriocheir japonicus. In the sandy parts the 
dredge supplied us with numerous fine specimens 
of a dark-brown, black Corbicula, but this bivalve 
appeared to be the only molluscous inhabitant of 
the lake. In the swampy pools of the immediate 
vicinity, however, we obtained two species of a 
pond-snail, or Planorbis, but could not detect the 
presence of either Ancylus or Limmea. 
We left our boat now to explore the woods 
around. In traversing the swampy plain in the 
