604 Browne.—Anomalous Traces in the Cone of E. maximum , Lam . 
out coming into contact with the axial stele, seems to point to the existence 
of a progressive reduction of the vascular system. Since the xylem of the 
sporangiophores consists practically exclusively of protoxylem this reduc¬ 
tion has chiefly affected the latter, though in some cases the phloem is also 
affected. 
2. Evidence that a reduction of the protoxylem system has occurred is 
supplied by the occasional presence in the steles of the cones of E. maxi - 
mum of strands of protoxylem ending blindly in a downward direction. 
3. Though apparently commoner in cones of E. maximum than in 
those of other species the anomalies described above are not confined to 
this species. 
Literature cited. 
Barratt, K.: A Contribution to our Knowledge of the Vascular System of the Genus Equisetum. 
Ann. Bot., vol. xxxiv, pp. 201-35, I 9 2 °* 
Browne, I.: (1) A Second Contribution to our Knowledge of the Anatomy of the Cone and 
Fertile Stem of Equisetum. Ibid., vol. xxix, pp. 231-64, 1915. 
- : (2) A Fourth Contribution to our Knowledge of the Anatomy of the Cone and 
Fertile Stem of Equisetum. Ibid., vol. xxxv, pp. 427-56, 1921. 
