170 THE AMERICAN MONTHLY [September, 



have from the dawn of animal life on the earth to the present played a lead- 

 ing part in the gi'eat problems and progress of the world. Biological evi- 

 dence is irresistible in proof that the first manifestation of animal life was 

 protozoic ; that the capabilities of development on this type were finally ex- 

 hausted, and that there radiated from the protozonic line, at different stages, 

 certain metozoic types. All through the ages of change they have kept per- 

 sistently to their work. The heat and drouth of summer or the frosts of 

 winter cannot destroy them ; when the water of the transient streams dis- 

 appears or food fails, they simply wrap about their frail bodies an imper- 

 vious mantle to retain their own moisture and fall asleep until returning 

 favorable conditions restore them to activity ; then again the battle of life 

 goes fiercely on beneath the surface. Each feeds ravenously upon unicellular 

 jolants, mercilessly on those of its kind smaller than itself, and in turn is des- 

 tined to be swallowed by one that is larger. Notwithstanding this inevitable 

 destruction, their prodigious powers of multiplication and reproduction ever 

 maintain them against the vicissitudes of climate or the distress from enemies. 

 This invisible link uniting the animal to the vegetable, and this to the minei'al, 

 incessantly at work, is found everywhere that moisture abounds. 



Saville W. Kent has gracefully said : — ' Inappreciable individually to the 

 unaided vision, the countless hosts of the Infusorial world, more familiar, per- 

 haps, to the popular mind under the designation animalcules or animalcula, 

 surround us literally on every side. They abound in the full plenitude of 

 life alike in the running stream, the still and weed-grown pond, or the track- 

 less ocean ; nay, more, every dew-ladened blade of grass supports its multi- 

 tudes, while in their semi-torpid encysted or sporular state they permeate as 

 dust the atmosphere we breathe, and beyond question form a more or less 

 considerable increment of the very food we swallow.' 



But it is not altogether the invisible and theoretical that challenge our at- 

 tention and admiration ; mountain masses of limestone are their enduring 

 monuments. From the warm seas of remote geological ages to the cooler 

 seas of the present they have been separating from sea-water the carbonate 

 of lime and fixing the carbonic acid gas until it is manifest that they have 

 done more than all other life towards preparing the present state of the modi- 

 fied crust of the earth. At the same time they have recorded in the rocky 

 volumes by their entombed shells much of the history of the past. 



This Society of microscopists has from the first kindly received, discussed 

 and published contributions to our knowledge of the various groups of the 

 simplest plants and animals ; hence, it seems appropriate to briefly enunciate 

 some of the chief problems, pertaining to the Protozoa, which are open to 

 us for investigation — problems to the solution of which the future work of the 

 Society should contribute. Obviously, the first works to be accomplished by 

 American students of the group are the identification of the species, naming' 

 describing, and figuring the new species and genera, recording the distrib 

 tion and habitats, and the presentation of the same in available publicatir'^^" 

 It is with pleasure and pride that we justly claim that in these lines the '''^\ 

 is going forward vigorously, although the number of students is limited' ^'^"» 

 thus far, almost exclusively restricted to fresh-water and parasitic 'Oiiris. 

 The results already recorded plainly show that the protozoic fauna of ^ui in- 

 land waters is extremely rich, presenting many characteristic and i^^^j!^i*\ 

 species. Many of our numerous species are undoubtedly identical '^\':^' ^^ 

 but slightly from European species, so slightly that I have not c('"^'^^*"?^^ 

 them of specific value, whilst many more are ^^erfectly distinct, r ^ • _ V' 

 Stokes, who has described more of our species than any one els"' '^'^^ ^^^" 

 that the species in the sphagnous swamps of New Jersey are r^ostly new. 

 The many unique forms he has brought to light appear to justifv' *"^ conclu- 



