Skinning-knife: The handle of this knife should be round, and the blade does not close.
Skull of bird (side view): Dotted line from A to B shows cut to be made in removing back of skull to give access to brain.
Skull of bird, under side: Dotted lines A, A, A, show cuts to be made in removing a triangular piece of bone and muscle, to which the whole or a portion of the brain will adhere.
Dissection of a song sparrow, showing male organs of reproduction: 1 and 2, lungs; 3, 3, testicles. The four organs below these are the kidneys.
Dissection of a song sparrow, showing female organs of reproduction: 4, lungs; 1, 1, small yellow glands, present in both sexes; 2, ovaries; 3, oviduct. These last four figures are merely diagrams, only sufficiently accurate in outline to convey an idea of the position of the parts indicated.