50 



favorable environment serve their ends; adaptations whether of 

 structure as examined "by the anatonist and taxonomist, of stages in 

 develooment, as seen by the enibryologlst, of habits, to be traced 

 by the' ecologist, or of vital processes, which fall within the 

 province of the physiologist. For the Oceanic Biologist, however, 

 the most productive subjects group around the animal forms and 

 habits that have developed, free on the one hand from the stimulus, 

 and on the other free from the limitations that are imposed by the 

 necessity of guarding against unfavorable surroundings. 



This freedom we see illustrated by the fact that all of the 

 phyla of the animal kingdom, now recognized, are at home in the sea; 

 whereas only seven of them have been able to conquer the terrestrial 

 environ;nent. 



The fac-c that the ocean is the home of the oldest and simplest 

 types of the various Phyla, and the Exclusive home of at least one 

 of the latter^ explains why the co-7iparative anatomist must have 



1. Of a second, also, if the Ctenophora be considered a separate 

 Phyliim . . 



access to marine organisms. The embryologist profits for the sar.e 

 reason, while for him certain marine forms, Selachians, Echidoderms, 

 Ctenophores, and many others, are classic material. When he turns 

 to experim.ental analysis he finds the eggs of Echinoderms, 

 Nemerteans, certain marine Annelids, Molluscs, and fishes better 

 fitted for studies of fertilization, and cleavage than any others, 

 both because they can be obtained in unlimited quantities, and 

 because they are laid and will develop in sea water over considerable 

 ranges of temperature, they are suitable for experimental procedure. 

 Contrast this v/ith the scarcity in niimber, and inaccessibility to 

 experiment, of the eggs of m.aimr.als. Except in the water, further- 

 more, no eggs are laid v;ithout extraneous protective devices. 



Oiving to the inherent suitability of the ocean as a home for 

 life, va.rious marine organism.s offer unique opportunities for 

 biological studies there, and this has been the consideration that 

 has lei to the existence of Marine Biolo.^^ical Stations. The history 

 of these begins with the Naples Station founded by Anton Dohrn in 

 1373, and with the Penilcese Station established by Louis Agassiz 

 during that same year. Since that time m.arine laboratories, to 

 exploit the advantages offered by marine organisms, and therefore 

 contributing to the biologic aspects of oceanography have multiplied 

 in Europe a.nd. America, Some of them have been associated with 

 economiic, especially Fisheries investigations; others, among w'lich 

 the Naples and T^oods Hole Stations are conspicuous, have served as 

 headquarters for theoretical problems, 



2. Marine Physiology 



The general ph^rsiologist, whether he works with m.arine, 

 with terrestrial, or with fresh water anim.als, seel:s a better under- 

 standing of the life processes that are comm,on to all animals and 

 plants, and of the ways in which the basic properties of protoplasm 

 are translated into all the complex manifestations of anim.al and 

 plant life that we see about us, on the basis of what can be learned 



