| HAECKEL: HIS LIFE, WORK, AND COMPANIONS 175 
hundred years afterwards by the telescope of Galileo, and 
accepted as it was by the reason of the learned and common 
sense of the multitude, was no nobler contribution to a 
“knowledge of the universe than was made by the biologists 
of the nineteenth century. Herchel’s nebulz and Ehren- 
berg’s monads may well excite in thoughtful minds admir- 
ation and reverence, those by their grandeur, these by their 
minuteness ; for both make known vast regions of the great 
universe which, so far as human records show, were never 
before unveiled to mortal vision. 
Following the wish of his father, Haeckel studied 
medicine. But the bent of his mind was to the study of © 
zoology ; and the works of Goethe, Alexander Von 
Humboldt, and Schleiden, further influenced him in that 
direction. At that time in Germany a band of; notable 
men, by their skill and industry, did much to make 
biology a new science. Of this group was Von Baer, by 
birth a Russian, whose ovological discoveries still keep his 
name famous. With them also were Schleiden and 
Schwann, rioted for their respective discoveries in the cell- 
structure of vegetable and animal life ; and Virchow, who 
first turned the cell-theory to account in pathological inves- 
tigation. Among others of that band were Kolliker, the 
foremost histologist of his day ; and Johann Mueller, often 
referred to as the father of modern physiology. All these 
men were personally known to Haeckel, and several of 
them were his intimate friends. 
Gegenbaur, the comparative anatomist, in 1853 told 
Haeckel that marine life could be profitably studied on the 
Mediterranean coast, and first kindled in him the desire to 
visit the Strait of Messina. Johann Mueller, by virtue of 
his strong personality and professional skill, did much to 
mould the character of Haeckel. For many years Mueller’s 
portrait had a place over Haeckel’s desk ; and he wrote to 
a friend: ‘‘ Whenever I get tired I look at it and gain 
fresh strength.’’ He went to Heligoland with Mueller on 
