LIST OF ILLUSTRATIONS. 



Portrait of Spencer F. Baird, LL. D. (Plate), 

 Intestine of the Craj-fish (Plate), .... 



Injecting apparatus with modified injecting jar (Figure) 



Sedentary fresh-water Peritricha, . 



Thread-cells of Hydra (Plate), 



Slide for Soap Films (Figure), 



Fresh-water Pol jzoa (Plate), 



Smut of Wheat and Oats (Plate). 



Black Spot (3 Figures), 



Ovary of the Cray-fish (Plate), 



Protococcus (14 Figures), 



Rinnbock's Slide of Arranged Diatoms (Plate), . 



Scales of Butterflies and Moths (Plate), 



Leeuwenhoek's Miscroscope, front and back views (Figure), 



Egg mass of Snail (Figure). ..... 



Embryo of Snail (Figure), ...... 



Spider's Foot (Figure), ...... 



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