DIRECTIONS FOR PLACING THE PLATES. 



Frontispiece and Engraved Title to face each other, and precede the 

 printed title-page. 



PLATE 



II. Fossil Infusoria to face page 154 



IV. Sponges, Spicula from n 175 



V. Zoophytes 194 



VI. Echino-dermata, &c. ...... 252 



VII. Proboscis of Fly 286 



VIII. Tongue, &c. of Drone-fly 296 



IX. Antenna, &c. of Moth 304 



X. Scales from Wings of Butterflies ... 306 



XL Parasites 326 



XII. Animal Structures 344 



XIII. Animal Tissues 352 



XIV. Human Skin and Hair 360 



XV. Vegetable Cells, &c 394 



XVL Vegetable Structures 424 



