MliS. COATES'S BATH. 79 



able to hold its own, I put one of them in the same 

 vessel. Next morning it was gone, and nothing was 

 left of it but the two sickle-shaped jaws, which were 

 lying at the bottom of the vessel. At last they took 

 to eating each other, and I have now but one survivor, 

 which, as may be expected, is a very large and fine 

 specimen. It changed to the pupal state while in my 

 possession, but is just as ravenous as it was when a 

 larva, and as it will be when it becomes a dragon-fly. 



Within this little pond are many species of caddis 

 and several of May-flies — at least, of these insects in 

 their preparatory condition. A really good collection 

 uf caddis-tubes can be procured from this spot, and I 

 was rather surprised to find in it the curved and conical 

 tubes of the Sericostoma, which are made of sand and 

 tiny fragments of stone. May-fly larvse also I found in 

 tolerable plenty, and obtained them by the simple pro- 

 cess of breaking up the mud of the bank, and catching 

 them as they issued from their dwelling tunnels. These 

 burrows are made in the soft muddy bank, and are 

 shaped like the letter 3 laid horizontally, so that the 

 inhabitants can pass in at one entrance and out at the 

 other. As for larvae of gnats and other flies, they 

 simply swarm, and are present in such numbers that to 

 give even a cursory description would take ten times 

 the apace that can be spared. The aquatic Crustacea 

 are in great numbers, and within the compass of that 

 tiny pond may be procured enough specimens to give 

 a laborious naturalist work for a year or two. Leeches, 



G 



