XIV CONTENTS. 



CHAPTER XVII. 



VAUCHERIA. 



Zoogonidia of vaucheria, 248. Sexual reproduction in vau- 

 cheria, 249. Vaucheria sessilis, the sessile vaucheria, 250. 

 Sexual organs of vaucheria, Antheridium, 251. Oogonium, 

 252. Fertilization, 253. The twin vaucheria (V. geminata), 

 254. Vaucheria compared with spirogyra, 255 page 109 



CHAPTER XVIII. 



COLEOCH,«TE. 



The shield-shaped coleoch^te, 257. Fruiting stage of coleo- 

 chsete, 258. Zoospore stage, 259. Asexual reproduction, 

 260. Sexual reproduction, oogonium, 261; antheridium, 

 262. Sporocarp, 263. Comparative table for spirogyra, 

 vaucheria, oedogonium, and coleochsete, 264 page no 



CHAPTER XIX. 



BROWN AND RED ALG^. 



Brown algae (phaeophyceae), 266. Form and occurrence of fucus, 

 267. Structure of the conceptacles, 268. Fertilization, 269. 

 The red algae, 270. Gracillaria, 271. Rhabdonia, 272. 

 Principal groups of algae, 273 page 115 



CHAPTER XX. 



fungi; moulds; water moulds; downy mildews. 



Mucor, 275. Asexual reproduction, 276. Sexual stage, 277. 

 Gemmae, 278. Water moulds (saprolegnia), 279. Appear- 

 ance of the saprolegnia, 280. Sporangia of saprolegnia, 

 281. Zoogonidia of saprolegnia, 282. Sexual reproduction 

 of saprolegnia, 283. Downy mildews, 285 page 120 



CHAPTER XXI. 



fungi {contimieJ); rusts; ascomycetes. 



Wheat rust (Puccinia graminis), 289. Teleutospores of the 

 black-rust form, 290. Uredospores of the red-rust form, 

 291. Cluster-cup form on the barberry, 292. Spermagonia, 



