LIST OF ILLUSTRATIONS xi 



FIG. PAGE 



154. A germinating spore of Riccia (after Campbell), to shew the manner 



of space- partitioning in the cellular tissue .... 372 



155, 6. Theoretical arrangement of successive partitions in a discoidal coll 373 



157. Sections of a moss-embryo (Kienitz-Gerloff) 374 



158. Various possible arrangements of partitions in groups of four to eight 



cells ! .... 375 



159. Three modes of partitioning in a system of six cells . . . 376 



160. 1. Segmenting eggs of Trochus (Robert), and of Cynthia (Conklin) . 377 

 162. Section of the apical cone of Salvinia (Pringsheim) . . . 377 

 163, 4. Segmenting eggs of Pyrosom.a (Korotneff), and of Echinus (l)riesch) 377 



165. Segmenting egg of a cephalopod (Watase) 378 



166, 7. Eggs segmenting under pressure: of Echinus and Nereis (Driesch), 



and of a frog (Roux) . 378 



168. Various arrangements of a group of eight cells on the surface of a frog's 



egg (Rauber) 381 



169. Diagram of the partitions and interfacial contacts in a system of eight 



cells 383 



170. Various modes of aggregation of eight oil-drops (Roux) . . 384 



171. Forms, or species, of Asterolampra (Greville) 386 



172. Diagrammatic section of an alcyonarian polype .... 387 



173. 4. Sections of Heterophyllia (Nicholson and Martin Duncan) . . 388,9 



175. Diagrammatic section of a ctenophore (Eucharis) .... 391 



176, 7. Diagrams of the construction of a Pluteus larva . . - 392, 3 

 178, 9. Diagrams of the development of stomata, in Sedum and in the 



hyacinth ........... 394 



180. Various spores and pollen-grains (Berthold and others) . . . 396 



181. Spore of Anthoceros (Campbell) . 397 



182. 4, 9. Diagrammatic modes of division of a cell under certain conditions 



of asymmetry .......... 400-5 



183. Development of the embryo of Sphagnum (Campbell) . . . 402 



185. The gemma of a moss [do.) ........ 403 



186. The antheridium of Riccia {do.) 404 



187. Section of growing shoot of Selaginella, diagrammatic . . . 404 



188. An embryo of Jungermannia (Kienitz-Gerloff) .... 404 



190. Develoj^ment of the sporangium of Osimmda (Bower) . . ■ 406 



191. Embryos of Phascum and of Adiantum (Kienitz-GerlolT) . . 408 



192. A section of Girardia (Goebel) 408 



193. An antheridium of Pteris (Strasburger) ....-■ 409 



194. Spicules of Siphonogorgia and Anthogorgia (Studer) . . . 413 

 195-7. Calcospherites, deposited in white of egg (Harting) . . ■ 421,2 



198. Sections of the shell of My a (Carpenter) 422 



199. Concretions, or spicules, artificially deposited in cartilage (Hartmg) 423 



200. Further illustrations of alcyonarian spicules: Eunicea (Studer) . 424 

 201-3. Associated, aggregated and composite calcospherites (Harting) . 425,6 



204. Harting's "conostats" "^27 



205. Liesegang's rings (Leduc) .....••• 428 



206. Relay-crystals of common salt (Bowman) 429 



207. Wheel -like crystals in a colloid medium (do.) . • • 429 



208. A concentrically striated calcospherite or spherocrystal (Harting) . 432 



