156 THE ESSEX FIELD CLUB. 



Mr. W. Cole exhibited some examples of a series of species of butterflies 

 which were intended to be placed in the Museum to illustrate the theory of 

 Mimicry amongst insects. 



He also exhibited some specimens of the curious mollusc, Petricola 

 pholadiformiSy which had been presented by Mr. J. E. Cooper and Mr. A. S. 

 Kennard. Mr. Cole and Mr. Kennard made some remarks upon the species, 

 which are embodied in a " Museum Note" in the present part of the Essex 

 Naturalist. 



Dr. Thresh read a paper by Miss May Thresh on " Manganiferous 

 Nodules in the Boulder-clay of Essex." This paper is printed in the present 

 part, aiite p. 137. 



Mr. T. S. Dymond, F.I.C., made some extended remarks upon this 

 paper which are printed ante p. 139, and a short discussion upon it was carried 

 on by Mr. Dalton, F.G.S., Mr. D. Howard, F.C.S , and Mr. J. W. Sajter. 



The Secretary said that he had received some little time back a paper by 

 Mr. J. P. Johnson on a Manganiferous Deposit in the Thames Valley Drift at 

 Ilford, which was already in print, and which would appear at the same time 

 as Miss Thresh's paper {ante pp. 135-6). 



On the proposal of the President, who remarked that the paper was a 

 most interesting piece of work, a cordial vote of thanks was passed to Miss 

 Thresh. 



Mr. Martin Hinton read a paper prepared by himself and Mr. A. S . 

 Kennard entitled " Contributions to the Pleistocene Geology of the Thames 

 Valley. L The Grays Thurrock area, Part H.," being the continuation of the 

 paper already published in the Essex Naturalist, Vol xi., pp. 336-370. 



A discussion on the paper took place, carried on by Mr. T. V. Holmes, 

 F.G.S., Mr. Dalton, F.G.S., Mr. Rudler, F.G.S., Mr. J. W. Salter, F.G.S., 

 and the President. Mr Hinton replied, and the authors were unanimously 

 thanked for their communication. 



In the absence of the author, Mr. C. D. Soar, F.R.M.S., Mr. Scourfield 

 read a paper on " The Water-Mites (Hydyachnida) of Epping Forest." 



The paper was illustrated by many beautiful coloured drawings, done 

 from nature by Mr. Soar, and Mr. Scourfield exhibited some specimens of 

 Water-Mites under the microscope. 



Both Mr. Soar and Mr. Scourfield were thanked for the paper, and the 

 meeting ended. 



