80 MORPHOLOGICAL DEVELOPMENT. 



viciualities are indefinite, the formation of major individu- 

 alities out of them, naturally leaves less conspicuous traces. 



Be this as it may, however, in such types of Protozoa as 

 the Thalassicollce, we find that though there is reason to re- 

 gard the aggregate as an aggregate of the second order, yet 

 its divisibility into minor individualities like those just de- 

 scribed, is by no means manifest. Fig. 140, representing 



iitff) 



Splmrozoum punctatum, one of this group, illustrates the diffi- 

 culty. Only by some license of interpretation, can we regard 

 the " celheforni bodies " contained in it, as the morphological 

 units of the animal. The jelly-like mass in which they are 

 imbedded, shows no signs of being divisible into portions 

 having each a cell or nucleus for its centre.* Comparison of 

 the various forms assumed by creatures of this type, suggests, 

 contrariwise, that the homogeneous sarcode is primary, and 

 its included structures secondary. Among the 



Foraminifera, we find evidence of the coalescence of aggre- 

 gates of the first order, into aggregates of the second order. 

 There are solitary Foraminifers, allied to the creature repre- 

 sented in Fig. 134. Certain ideal types of combination 



* This statement seems at variance with the figure ; but the figure is very in- 

 accurate. Its inaccuracy curiously illustrates the vitiation of evidence. When I 

 saw the drawing on the block, I pointed out to the draughtsman, that he had 

 made the surrounding curves much more obviously related to the contained bodies, 

 than they were in the original (in Dr Carpenter's Foraminifera) ; and having 

 looked on while he in great measure remedied this defect, thought no further care 

 was needed. Now, however, on seeing the figure in the printer's proof, I find 

 that the engraver, swayed by the same supposition as the draughtsman that such 

 a relation was meant to be shown, has made his lines represent it still more de- 

 cidedly than those of the draughtsman before they were corrected. Thus, vague 

 linear representations, like vague verbal ones, are apt to grow more definite 

 when repeated. Hypothesis warps perceptions as it warps thoughts. 



