182 STUDIES IN GENERAL PHYSIOLOGY 
upper surfaces of the lateral branches, and were therefore 
directed, not toward the old, but toward the new tip of the 
animal. Furthermore, the acute angle at which the new 
lateral branches arose from the main stem opened toward the 
zenith; the convexity of the new branches was also directed 
toward the zenith. In this way animals were therefore 
formed which ended in a tip at both ends—animals that were 
biapical; just as though one were to grow a new top upon a 
tree in place of the roots, without, however, allowing the old 
apex to go to pieces. In the specimens illustrated in this 
paper the tips are still relatively small. My stay at Naples 
was too short to allow me to wait for them to reach maturity. 
3. When stems of Aglaophenia which had been cut off 
close to the roots, the tips of which, however, were left intact, 
were suspended vertically and in an upright position in 
water, a new root was invariably formed at the basal end, 
and never a new tip. 
It therefore seems that the position of the stem of Aglao- 
phenia determines to a certain extent whether a heteromor- 
phosis, or only a regeneration, of the lost part occurs at the 
basal cut end. 
4, This fact is further supported by the following obser- 
vation: When stems of Aglaophenia from which the tips and 
roots had been cut were suspended vertically in the aquarium 
so that both cut ends were surrounded by water, a root was 
always formed upon the end directed downward, it mattered 
not whether it was the basal or apical end. 
In many cases branches were formed at the end directed 
upward, yet in other cases a root was formed here also. A 
root was formed most frequently upon the ends directed 
upward when the basal end of the stem was pointed in that 
direction; branches were formed most frequently when the 
apical end of the stem was directed upward. 
It is therefore possible to create bibasal Aglaopheniae, 
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