THE BUILDIXa OF AX AUTOTROPHIC FLAGELLATE 289 



plankton-cell in sea-water. He insists that it is in the vast, constant^ 

 ionized ocean that the first hazy rudiments of life began to be 

 (problems for the phj^sicist and chemist to unravel) ; that carbo- 

 h\^drates were formed and increased in complexity, thanks to the 

 peculiar linking properties of the carbon-atom, and led on to colloid- 

 formation ; that nitrogen was pressed into service and was added to 

 the mobile composition of the plasma; and that, when means had' 

 been evolved for utilising solar energy, an autotrophic organisation 

 had come into existence capable of producing an ever increasing out- 

 put of carbohydrate and proteid, and of carrying on life indefinitely. 

 The subject thus became a botanical problem. Owing to the scarcity 

 of nitrogen compounds in the sea, the manufacture of carbohydrates 

 was necessarily far in excess of the proteid synthesis, and consequently 

 tbere were great quantities of carbohydrate waste to be got rid of, 

 either in a soluble form, or by storage, or preferably as an insoluble 

 polysaccharide deposit on the periphery of the plant — thereby origin- 

 ating a mucilaginous or cellulose wall. Thus " chemical linkage " 

 and '* physical growth by adsorption " progressed. The plasma 

 prospered in the daylight, but by night it had to live upon its own 

 reserves ; in this wa_y katabolism was initiated and a certain indepen- 

 dence attained — an independence which conduced to the possibility 

 of animal life. The delicate plasma necessarily assumed a spherical 

 form by reason of surface tension. Surface tension and metabolic 

 activity would be associated with contractility. Further, a " differ- 

 entiation " of the plasma '• into at least three regions may be postu- 

 lated " : (1) the surface or plasmatic film ; (2) an illuminated 

 metaboHc zone — the chloroplasm ; (3) a central region — the nucleo- 

 plasm — living at the expense of the outer zones and free to assume 

 the control of the organism. As the spherical plankton-cell tends 

 to sink vertically, which would be fatal, a tremendous advantage 

 would be gained if the organism could contrive to rise up by growth 

 towards the lessening light. Thus polarity is assumed to have be- 

 come established — with the subsequent development of a flagellum, 

 however rudimentary, which served primarilj^ as an "anterior tractor- 

 mechanism " and subsequently became exploited in many cases as a 

 food-gatherer. A great advance was achieved when binarj^ fission 

 superseded the mere fragmentation due to sea-action, such fission 

 being presumed to originate in the deep-seated nucleoplasm where 

 starvation would first be felt. The author, in discussing failure and 

 death, argues that " under pressure of approaching dissolution new 

 departures . . . new racial improvements . . . ma}^ be . . . expected to 

 occur," namely, the evolution of sexuality, of the holozoic animal, of 

 benthic plants and animals. The later chapters treat of holozoie 

 nutrition, the origin of sexual fusion, the differentiation of flagella, 

 the formation of the cell-wall. 



Step by step the author works out his case, showing how in- 

 evitably phase has followed phase in the scheme of evolution — a 

 scheme which was " settled once for all time in the initiation of 

 minute forms of ultra-microscopic life, as the necessary outcome of 

 the physical and chemical organization of the aqueous phase of the 

 sea itself." Dr. Cbui-ch's pamj)hlet is written in a condensed style 



