J. D. Dana on Zoophytes. 337 
Arr. XXXIII.—On Zotphytes, No. V.; by James D. Dana. 
CLASSIFICATION OF ZoOPHYTES. 
General Remarks on Classification.—It has often been justly 
said, that there can be but one strictly natural classification in 
either of the organic kingdoms. Yet if we look upon any system 
presented in the usual order on paper, as correctly and completely 
the natural system, we greatly mistake nature; for the various 
affinities cannot be fully expressed on a plane surface. The lines 
are so many, and so interlaced, that to be understood, they must 
be conceived of as ramifying in space. The mind, proceeding 
properly to its work, determines first upon those qualities which 
are physiologically of the most fundamental importance : it fol- 
lows out the variations of structure under the grand divisions 
thus ascertained, fixing its attention successively upon qualities 
of a less and less general character ; it traces the species through 
the various modifications in these several particulars, marking out 
the lines of gradation in affinities, observing some, it may be, 
_ partly isolated and terminating abruptly, others graduating into 
way the network is finally completed to the mind’s eye. ~ 
When the relations are fully understood, we are ready to divide 
off into classes, orders, and the smaller subdivisions, cutting the 
threads here and there, as shall best exhibit the general character 
mek 
+ oy 1 Se 
boivViig Ui 
pa} 
R 7 5 WY siete! gi Mase 
equivalent importance and character. The institution of these va- 
te } 
display like anatomical preparations; but to illustrate the system 
Secon Sznizs, Vol. UI, No. 9.—May, 1847. 43 
