Illustrations xi 



FACT KG 

 FAG1 



A PAIR OF LADY-BIRD BEETLES FEEDING ON APHIDES OR GREEN-FLY . 662 

 Photos: J. J. Ward. 



SUMMER GREEN-FLY MULTIPLYING ON THE FLOWER OF THE SWEET-PEA 662 



HEDGEHOG DRINKING ..... . 663 



Photo: J. J. Ward. 



A BRACKET FUNGUS GROWING AS A PARASITE ON A BIRCH-TREE . . 663 

 Photo: F. R. Hinkins & Son. 



HAZEL STEMS STRANGLED BY HONEYSUCKLE ..... 666 



Photo: F. R. Hinkins & Son. 



THE LIVER-FLUKE THE CAUSE OF "LIVER-ROT" IN SHEEP (magnified 



about 4 times) 666 



Photo: J. J. Ward. 



A BUNCH OF ZOOPHYTE GROWING ON THE SHELL OF A HORSE-MUSSEL . 667 

 Photo: J. J. Ward. 



THE BLUEBOTTLE LAYING HER EGGS IN THE SLIT OF A DEAD BIRD'S BEAK 667 

 Reproduced from Fabre's The Wonders of Imtinct. 



Louis PASTEUR ........... 676 



Photo: Rischgitz Collection. 



METCHNIKOFF ........... 676 



Photo: Henri Manuel. 



A SPOT OF POND WATER AS IT APPEARS UNDER THE MICROSCOPE, SHOW- 

 ING VARIOUS FORMS OF UNICELLULAR PLANTS, ETC. .... 677 

 Photo: J. J. Ward. 



BLUE CHEESE MOULD .......... 677 



Photo: J. J. Ward. 



PROTOPLASM OF NUCLEUS WITH PART OF SURROUNDING PROTOPLASM, FROM 

 GANGLION CELL OF 'AN Ox (from Biitschli) ..... 680 



SECTION OF THE HEART OF A PINE BUD 680 



Photo: J. J. Ward. 



DIFFERENTIATION OF CELLS IN THE LENS OF A CHICK'S EYE . . .681 



From The Problem of Age, Growth, and Death, by Charles S. Minot 

 (John Murray). 



FOUR RED BLOOD CORPUSCLES AND A WHITE CORPUSCLE OF A FROG; 

 THE LATTER HAS ENGULFED A WORN-OUT RED BLOOD CORPUSCLE 

 (magnified 600 diameters) . 681 



From The Essential! of Histology, by Sir Edward Sharpcy Schufrr (Long- 

 mans, Green & Co.). 



