HAECKEL: HIS LIFE, WORK, AND COMPANIONS _ 89- 
life of the Indian Ocean towards the equator. In that 
object he succeeded ; though the heat and moisture of the 
tropics made preservation of his collections a task which 
sorely taxed his limited resources. 
For six weeks he lived and worked at the Singhalese 
fishing village of Belligam, on the south-eastern part of the 
island. There, cut off from European associations, and 
with none but native companions, he roamed the forest in 
quest of plants and animals, dived with natives to the bot- 
tom of the sea for corals, microscopically investigated his 
treasures, and with his own hands soldered them up in air- 
tight tin cases for future use. For all this strenuous work 
in tropical heat, during four months sojourn in Ceylon, he 
escaped without a day’s illness. These experiences, related 
as they are with vivacity and humour, and his notes on the 
physical geography of the island, and the tropical luxuriance 
of its fauna and flora, make Haeckel’s ‘‘ Visit to Ceylon’’ 
a pleasant, edifying book of travel. 
Early in his professional life Haeckel became convinced 
that accurate knowledge of cell-structure was the founda- 
tion of biological science ; and each fresh discovery con- 
firmed that conviction. Of vertebrates the fertilized germ- 
cell from which the race is perpetuated, is made up of cell- 
plasm and nucleus. In each such cell—though a mere 
speck—in some particulars like to other cells, there never- 
theless lurks the potentialities of its race, even, it is said, to 
the tendency in advanced life to develop special disease 
akin to that endured by its parents. The nucleus of such 
a cell contains granular matter, easily stained for micros- 
copic observation, and therefore named chromatin. 
Recently it has been learned that such chromatin separates 
into minute bodies known as chromosomes ; and to then 
has been attributed the chief function of heredity. Profes_ 
sor Thomson, of Aberdeen, has tabulated the actual number 
of such chromosomes peculiar to sundry species of living 
things. Forty years ago Haeckel’s teaching pointed the 
