Fic. 14.—A, hybrid larva of Spherechinus 9, and Echinus 6; front 
view. B, the same; oblique, side view. C, dwarf hybrid larva of 
Spherechinus 9 (non-nucleated egg fragment), and Zchinus 6, of 
pure Lchinus type. D, the same larva in side view. (After 
Boveri.) 
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