XX PROCEEDINGS OF THE 



The President inquired whether different species of butterflies could he dis- 

 tinguished by their scales. He quite agreed with Mr. Perkins that it would be 

 desirable to have a record kept of the rarer insects which might be found in the 

 county, and suggested that he (Mr. Perkins) might act as registrar. 



The Author replied that many, if not most, species of butterflies could be dis- 

 tinguished by their scales, when these were examined under the microscope. 

 He would willingly undertake the task of registering any observations on insects 

 that might be sent to him. 



The President announced that the Council had arranged with 

 the assistant-librarian of the Public Library that members might 

 exchange books any week-day, from 3 to 5, and from 7 to 10 p.m. 



Ordinary Meeting, 11th April, 1878. 

 Alfred T. Brett, Esq., M.D., President, in the Chair. 



The following lecture was delivered : — 



" On the Physical Characteristics of Minerals." By James U. 

 Harford. {Vide p. 104.) 



Specimens of minerals offering examples of all the different 

 characteristics mentioned, and models of crystals, etc., were ex- 

 hibited, and some experiments illustrative of the lecture were made 

 by the Author. 



The Honorary Secretary announced that the first donation of 

 microscopical slides had been received since the previous meeting, 

 five slides having been presented to the Society by Lieut. Croft, 

 F.L.S. He hoped other members would soon follow the example 

 set them by Mr. Croft. 



Field Meeting, 4rH May, 1878. 

 Cassiobury Park, Temple of Pan, and Langleybury. 



A numerous party, with a considerable majority of ladies, 

 assembled at the principal entrance to Cassiobury Park at 3 o'clock, 

 and, some in carriages, some on foot, proceeded through the Park 

 to the Swiss Cottage. 



As this was visited at the last field meeting in 1877, its rustic 

 grounds did not long delay the party. After crossing the river and 

 canal, and again entering the Park, the magnificent avenue of 

 lime trees, and the avenue of wych elms, about three-quarters of a 

 mile in length, which crosses it at right angles, were inspected and 

 admired. 



The members then left the Park, and, wending their way along 

 the picturesque wood- walks of the AVhippendale valley, crossed the 

 Rickmansworth road near the gamekeeper's cottage. Availing 

 themselves of the kind permission of the Earl of Clarendon, they 

 now plunged into the charming woods which extend in a north- 

 westerly direction towards Chipperfield. After rambling for some 

 time in these woods, the party assembled for a short rest at the 

 Temple of Pan, where refreshments, which proved to be very 



