48 [J"'y' IS"-'- 



Ath June, 1879. H. W. Bates, Esq., F.L.S., &c., Vice-President, in the Chair. 



The following were elected : Mr. J. Walhouse, F.R.A.S., of 9, Eandolph Crescent, 

 Maida Vale, an Ordinary Member ; Senor A. A. de Carvalho Monteiro, of 72, Rua 

 do Alcarion, Lisbon, as Foreign Member ; and Mr. C. H. Goodman, of Lesness 

 Heath, as Subscriber. 



Amongst the donations to the Library were Vol. i of Edwards's " Butterflies of 

 North America," specially coloured for the Society, and presented by the author ; 

 and Doubleday, Hewitson and Westwood's " Genera of Diurnal Lepidoptcra," pre- 

 sented by Mr. Dunning on the occasion of the 30th Anniversary of his election as 

 Member, and for which a special vote of thanks was carried by acclamation. 



Mr. McLachlan called attention to a notice by Prof F. A. Forel, published in 

 the Proces-verbaux de la Societe Vaudoise des Sciences Naturelles (oth Dec, 1877), 

 on the sculptured markings on cretaceous pebbles in Lac Leman, and exhibited two 

 plaster casts of sculptured blocks, one of Jurassic limestone, the other of white 

 chalk. These sculptured markings were at one time thought to be due to the 

 action of Mollusks or Algse, but Prof. Forel was of opinion that they were 

 really caused by Trichopterous larvae, some of which he forwarded, and which were 

 possibly those of the genus Philopotamiis. 



Mr. Meldola suggested that they might arise from the action of the carbonic 

 acid exhaled by the larvae. 



Sir S. S. Saunders communicated notes by M. J. Lichtenstein respecting the 

 transformations of Cantharis vesicatoria. (A condensed account, by M. Lichtenstein, 

 appears in our present No.). 



Mr. Meldola read a translation of a paper by Dr. Fritz Miiller on " Ituna and 

 Thyridia, a remarkable case of mimicry in Butterflies," published in " Kosmos " for 

 May, 1879. The author regarded it as a case of acquired resemblance, and that it 

 might belong to the category of those in which distasteful species are about equally 

 common, so that each step taken by either in more nearly approaching the other, is 

 of common advantage to both. Mr. Jenner Weir was of opinion that Dr. Miiller 

 had, in his remarks, placed too much importance upon the supposed inexperience of 

 young birds in detecting what insects were good for food, and what were not. In 

 his experiments with birds and larvae he had found that the former never attempted 

 to touch the distasteful larvae, hence acting under the influences of knowledge ac- 

 quired by heredity. 



Mr. Bates said the subject was one of intense interest, and those cases in which 

 species apparently protected by offensive secretions mimic others protected in a like 

 manner, were very difficult of explanation, and he did not tffink that Dr. Miiller had 

 cleared away all the stumbling blocks. He alluded especially to the manner in 

 which gaily coloured mimicking butterflies and moths in Tropical South America all 

 change their hues and markings together at every few hundred miles. 



Mr. J. S. Baly communicated a paper " On the differential characters of certain 

 closely-allied ChrysomelidcB." 



Prof. Westwood communicated " A decade of new Cetoniida^' and a paper on 

 " Some unusual monstrous insects." 



Mr. Distant read " Contributions to a knowledge of the Hemipterous Fauna of 

 Madagascar." 



