RECENT LITERATURE. 23 



series of Gastropacha quercifolia, L., bred from Surrey ova. — Mr. 

 W. Harrison, Centra furcvla, CL, bred from larvae obtained near 

 Sandwell Park. — Colbran J. Wainwright, Hon. Sec. 



KECENT LITERATURE. 



Eighteenth Annual Report of the Delegates of the University Museum 

 (for 1905). *90pp. 



Among the other Reports contained in this volume is that of the 

 Hope Professor of Zoology, Edward B. Poulton, D.Sc, M.A., F.R.S. 

 From this we gather that the number of specimens of all Orders comprised 

 in the Insect Collection is nearly 500,000. From a census taken by 

 Commander J. J. Walker in 1901, Lepidoptera exhibited a total of 

 112,149, and Coleoptera 194,434 ; in 1905 he. cast the number of 

 insects in the other Orders at 134,075. It will be seen then that the 

 Hope Department of the Oxford University Museum possesses an 

 exceedingly large amount of entomological material, and it is evident 

 that during the year 1905 the Professor and his staff have made very 

 considerable progress in the work of preparing, cataloguing, and 

 arranging this material so as to render it available for study. Besides 

 much other important work that has been accomplished, or in hand, 

 is the revision and arrangement of the Orthoptera by Mr. R. Shelford, 

 who has completed the Blattidae, and is now dealing with the other 

 groups. Mr. Hamilton H. Druce has named the Lycaenidae, and the 

 arrangement of the butterflies, as a whole, is nearly finished, the 

 Papilioninas and Hesperidre only awaiting attention. As the Professor 

 points out, however, " while one part is being arranged the others are 

 rapidly growing, so that a certain amount of adjustment and re- 

 arrangement will always be necessary." 



Melanism in Yorkshire Lepidoptera * By G. T. Porritt, F.Z.S. 



Mulanism in Lepidoptera is a subject upon which much has been 

 said and written, and many theories have been put forward as to the 

 how and wherefore ; but, as Mr. Porritt most justly remarked, " we 

 really know very little about it." He had no definite theory of his 

 own to advance, but he detailed a large amount of information con- 

 cerning a great number of species, which in Yorkshire, and parts of 

 Lancashire, are melanic, or exhibit a tendency to become so. Referring 

 to var. doubledayaria, the black form of Amphidasys betularia, he said that 

 in the South-west Riding this had become the dominant form of the 

 species, and in the same area the typical form was now quite rare. " It 

 is most curious, too, that in this species the black form appears to 

 have developed suddenly, i.e., it was not a gradual darkening, as no 

 intermediates were noticed in a wild state." 



* Paper read before the Zoological Section, and printed in the Eeport of 

 the British Association for the Advancement of Science, Section D. York 

 1906. 



