240 Journal New York Entomological Societv. [Vol. xvi. 



Society be instructed to spread on the minutes and communicate to the Board of Trus- 

 tees of the American Museum of Natural History and to Mr. Morris K. Jesup's 

 family, the sincere regret which the Society feels on losing one who manifested such 

 broad and unfailing interest in all matters pertaining to natural history and the natural 

 sciences in general." 



E. B. Southwick, 

 W. M. Wheeler, 

 Raymond C. Osborn, 



Committee. 



On motion the report was accepted. 



Mr. Dickerson announced that the Newark Society had planned an outing at 

 Great Piece Meadows, N. J., on Decoration Day, and invited the New York mem- 

 bers to cooperate. 



Mr. Engelhardt spoke on albinism and melanism among insects, illustrating the 

 subject with an interesting series of specimens. His remarks were in substance as 

 follows : 



Albinism is due to the absence of pigment. The term "albino " was first ap- 

 plied by the Portugese to the white negroes of west Africa ; it is now applied to any 

 individual in whom there is deficiency of pigment in the skin, hair or eyes. The 

 absence of pigment is normal in the polar bear, the northern white owl, etc. The 

 seasonal change of color in such animals as the white fox and ptarmigans is due to 

 cold and brought about by the formation of numerous air bubbles which tend to 

 conceal the pigment, the latter being rarely entirely absent in the hair or feathers. It is 

 doubtful whether albinism occurs among insects, unless cave insects and other sub- 

 terranean forms may be designated as such. Among Lepidoptera a number of white 

 varieties are recognized. Melanism is due to the excess of pigment and occurs among 

 insects, fishes, reptiles, birds and mammals. Moisture is given as a primary cause of 

 its appearance but many facts are still wrapped in doubt. The hot and moist atmos- 

 phere of the tropics and the cool damp climate of mountain regions and polar lands 

 both cause melanism. The black leopard of southern Asia is only a melanotic variety 

 of the common leopard. Butterflies and moths inhabiting mountain regions of high 

 altitude are usually darker than individuals of the same species living in the drier and 

 warmer lowlands. 



The following specimens were exhibited: Colias pkilodice 9 9 °f normal form 

 and albin c variety. Colias pkilodice $ g of normal form and melanotic variety. 

 The lafer were exceptionally fine examples, entirely suffused with black, captured 

 at Bethlehem, Pa., in August, 1907. Argynnis myrina $ $ , normal and melanotic 

 forms, the latter taken at Overbrook, N. J., May 30, 1907. Papilio glaucus and var. 

 turnus 9 9 ; the black form with upper wings entirely black and orange spots on 

 lower wings absent. Sabulodes transversata 9 9 > normal and melanotic forms. 

 Cicindela partrnelis and C. consent anea, Cicindela rugifrons and C. modest a. Dic- 

 tyophorus micropterns ; red form from Florida and black form from Texas. Melitiea 

 rubicunda $ $, normal form and aberration with yellow spots entirely absent. Meli- 

 tcea mcEglashani $ $ , normal form and aberration with red spots entirely absent 

 Colias behrii $ , illustrating typical mountain species. 



In ihe discussion which followed the reading of Mr. Engelhardt's paper, Mr. 

 Schaeffer stated that the white color of the Colias var. was due not to absence of pig- 

 ment, but to the abundance of white coloring matter present. 



