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very similar in all the seas, but in numerous in- 
stances identically the same. ‘The Atlantic corre- 
sponds marvellously with the Mediterranean, and 
the Indian and Pacific Ocean, have very universally 
the same genera with the Atlantic. He finds a 
community of infusorial life between the Arctic 
and Equatorial regions. Besides the equable tem- 
perature in which they exist, and in which they 
move, subject to a general diffusion from the whole 
region of waters being traversed by great streams 
und currents, which are so many ocean rivers, — 
much of the universality is due to the phenomena 
of geology, as Humboldt has shewn. ‘ Previous 
to the existence of the human raee, the action of 
the interior of the globe upon the solid crast which 
was increasing in volume, must have modified the 
temperature of the atmosphere, and rendered the 
whole surface capable of giving birth to those pro- 
ductions which ought to be considered as tropical, 
since by the effect of the radiation and refrigeration 
of the exterior the relation of the earth to a central 
body, the sun, began almost exclusively to deter- 
mine the diversity of geographical latitudes.” 
in the infusorial department, under a heading,— 
“ Jamaica,” Dr. Schmarda has made numerous 
drawings of objects determined under the Micro- 
scope. The drawings are magnified somewhere 
about fifty fold. 
