46 



THE ESSEX FIELD CI.UB. 



Epping Forest. Almost immediately after the stumps were cut the slimy layers 

 of this curious organism had spread with rapidity over the sap-bathed surface. 

 The fungus consisted of masses of nalved protoplasm, having considerable powers 

 of movement, like the Amoeba, although botanists now consider the Myxomycetes 

 to be fungal, and net animal, in their nature. • 



Mr. H. C. Snell exhibited several specimens of the somewhat rare subter- 

 ranean slug, Teslacella scutiihim, which he had found during this season's spring- 

 digging in his garden at Buckhurst Hill. The creature is very interesting in its 

 habits, being carnivorous, and feeding upon earth-worms, which it hunts under- 

 ground. Mr. Cole remarked that Mr. Crouch had found the slug at Wanstead, 

 and he himself had taken it somewhat abundantly in an old garden at Stoke 

 Newington, many years ago. 



Mr. Oldham exhibited species of Noctucr captured in Epping Forest during 

 the last autumn, and Mr. Wire explained an admirable sj'stem he had devised for 

 mounting, indexing, and grouping in volumes, newspaper cuttings, leaflets, and 

 small pamphlets. 



Prof. Meldola said that Col. Swinhoe, M.A., F.L.S., of Oxford, had intended 

 to give them a lecture on " Protection in Nature " ; but most unfortunatel}-, 

 owing to sudden illness, he was unable to leave home. In the kindest manner, 

 their member, Mr. E. B. Poulton, M.A., F.R S., had come to their rescue, 

 travelling specially from Oxford that afternoon to deliver a lecture on very 

 similar lines to those which had been proposed by Col. Swinhoe. 



Mr. Poulton then delivered a most interesting address, which was illustrated 

 by a large number of coloured pictures from original drawings (shown b}- the 

 oxy-hydrogen lante n) of various animals considered from the point of view of 

 tlieir p )wers of concealment or other modes of protection from their enemies. 

 Mr. Poulton clearly showed that not only have animals the power of concealment 

 when the conditions of environment aie constant, as when they resembled sand, 

 rocks, ba k of trees, etc., but that many animals, particularly insects, had the 

 power of adaptation to varying surroundings. The colour of oceanic animals 

 frequently assimilated in a truly wonderful way to the tint of the sea or the 

 prevailing colour of the seaweeds, etc. Land animals often resembled the sand, 

 rocks, or twigs of trees, or dead leaves, etc., upon which they rested. The 

 lecturer explained a series of examples drawn from a wide range of animal life, 

 showing the modes of concealment acquired by fish, Crustacea, spiders, insects, 

 etc. The most interesting part of the address was that in which Mr. Poulton 

 detailed the results of his own researches upon the varying colour relations of 

 caterpillars and chrysalids with their surroundings. Perhaps the most remark- 

 able e-xample was the caterpillar of our common " Peppered moth " (^Atnpliydasis 

 hetularia), which varied in a most startling way in accordance with the prevailing 

 tint of the twigs or leaves upon which it happened to rest. By a series of skil- 

 fully conducted experiments, Mr. Poulton had proved that it was possible to 

 obtain from the same batch of eggs of the moth, caterpillars differing most 

 widely in colour, simply by varying the tints of the surrounding objects. 

 Cocoons and chrysalids of moths and butterflies were shown to vary in a similar 

 manner. The lecturer showed that the variation was not the effect of food, as had 

 been formerly supposed, but thatjt was the result of the action of light upon the 

 superficial tissues of the caterpillars, whereby they were rendered opaque or 

 transparent, so concealing or revealing the colours of the deeper situated tissues 

 in the bodies of the animals. Mr. Poulton concluded by exhibiting the coloured 



