Youatt, Mr., on the development of the horns in cattle.

Yura-caras, their notions of beauty.

Zebra, rejection of an ass by a female; stripes of the.

Zebus, humps of.

Zigzags, prevalence of, as ornaments.

Zincke, Mr., on European emigration to America.

Zootoca vivipara, sexual difference in the colour of.

Zouteveen, Dr., polydactylism; proportion of sexes at Cape of Good Hope; spiders attracted by music; on sounds produced by fish.

Zygaenidae, coloration of the.

THE END.