ALTERNATE GENERATION. 43 
afflicted with tape-worm, issue so-called somites or seg- 
ments of the tape-worm. These somites are usually 
filled with such an extraordinary number of ova that 
they seem like mere packets of eggs. It appears, how- 
FIG. 3. 
ever, from the evolutionary history of the tape-worm, 
and its relations ‘with other annulosa, namely with 
leeches and Turbellaria, that notwithstanding their in- 
completeness and deficiency of organs, these somites are 
equivalent to sexually mature individuals ; or, according 
to Haeckel’s definition, are endowed with personality. 
If the tape-worm now comported itself like most other 
animals, somites would be directly developed from its 
eggs. But to this there is a very circuitous proceeding. 
