988 
INDEX. 
Weierstrass, Abelian functions after him, 347 (see Forsyth). 
Wertheim, experiments of, on elasticity discussed, 14, 128. 
Williamson (W. C.). On the Organization of the Fossil Plants of the Coal-Measures.—Part XII.. 459.— 
Psaronius Renaultii, 464; Zygosporites, 464; Calamites, 465; Lepidodendroid plants, 465; Halonia, 
466; Sporocarpon, 469; Dadoxylon, 469; index to the plates, 471. 
Wilson (E. B.). The Development of Renilla, 723.—Segmentation of the egg, and formation of the 
germinal layers, 72 8; development of organs and tissues, 760; development of the colony, 782; 
general considerations, 797 ; appendix, 808 ; explanation of figures, 808. 
Y. 
Yttrium, the detection and wide distribution of, 891. 
Z 
Zygosporites, 464 (see Williamson). 
