038 



INDEX 



VORTICELLA : occurrence and 

 general characters, 269 ; struc- 

 ture, 269 ; reproduction, 273 ; 

 conjugation, 274 ; means of 

 dispersal, 274 ; encystation, 

 275 ; spore-formation, 276 ; 

 metamorphosis, 276 ; prac- 

 tical directions, 277 



Vulva, 487, 540 



W 



Waste-products, 8, 66, 249 

 White matter of brain and 



spinal cord, 156, 160, 167 

 Wolffian body, see Epididymis 



duct, 603 



Work and waste, 66, 148, 234 

 Worms, 349 

 Wrist, see Carpus 



X 



Xiphisternum, 48, 500 



Yellow cells of Earthworm ,331, 



335, 34i 

 \olk, yolk-granules or spheres, 



195, 564, 569 ; and see under 



various types 

 Yolk-cells, 200, 202 

 Yolk-plug, 201, 581 

 Yolk-sac, 470, 582, 586 



Zona radiata, 586 



Zoochlorella., 304 



Zooid, 277, 309; and see Mega- 



zooid and Microzooid 

 Zoology, i 



Zoophytes, see Hydroid polypes 

 Zygapophysis, 36, 498 

 Zygoma, zygomatic arch, j.t. 



195 

 Zygote, 197- -J5 1 - 2 75- 284 



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