5 2 I 
Anatomy of Teratological Seedlings. /. 
the phloem groups on either side of it. In almost every example of this 
type the protoxylem disappears first, followed at a later stage by the 
Fig. i 3. a, b, c. Tetracotylous and hemitetracotylous seedlings. 
Fig. 14. a-e. Tetracotyl showing reduction from tetrarchy to diarchy by fusion. 
Fig. 15. a-e. Tetracotyl showing reduction from tetrarchy to triarchy by fusion. 
metaxylem (cf. Compton [ 4 ], Cannabis sativa y Tricotyl D). In one case 
only does the metaxylem disappear, first leaving an isolated protoxylem 
