18 FEBRUARY 1905, Page 15

[TO THE EDITOR OF THE " SPROPATOR.")

STB,—The cases of the bird and the insect mentioned in your last week's article on the above subject are scarcely parallel. The mason wasp that visited the keyhole was a different individual from that of the previous year, as the little lives of these insects are rounded within the compass of a year. It seems to have been a case of hereditary instinct in the species, convenient apertures such as keyholes being well impressed on the "racial memory."—I am, Sir, &c., F. M.