NOTES ON CALAMOPITYS. 231 
Unerr, 1856.—R. Richter & F. Unger: Beitrag zur Paläontologie des Thüringer Waldes; 
2ter Theil, von F. Unger, Schiefer und Sandstein-flora. Denkschriften der K. Akad. 
d. Wiss. Wien, Band xi. p. 139. 
WEBER & STERZEL, 1896.—O. Weber & J. T. Sterzel: Beiträge zur Kenntnis der 
Medullosew. Ber, d, naturwiss. Gesellschaft zu Chemnitz, Bd. xiii. 
Zauussky, 1911.—M. D. Zalessky: Etude sur l'Anatomie du Dadoxylon Tchihatcheffi. 
Mém. du Comité Géologique, Nouvelle Série. Livraison 68. Petrograd. 
ZALESSKY, 1911*.-—M. D. Zalessky : Études paléobotaniques. lre Partie: Note préliminaire 
sur le Cenoxylon Scotti, nov. gen et sp., p. 13. 
EXPLANATION OF THE PLATES. 
All the figures are photographic and frequently need to be examined with a lens. 
PLATE 6. 
Calamopitys americana. 
(From photographs by Mr. W. Tams.) 
Series, from below upwards, to show division of the leaf-trace. All the 
figures (except 2 and 4) are x about 7. 
Fig. 1. Part of stele, with much secondary wood. The single trace (/.t.) is at the margin 
of the pith. Section 1 (S. 2944). 
2. Primary xylem-strand of leaf-trace with adjacent secondary wood from same 
Section. pæ., the partly disorganized protoxylem of the strand. x 37. 
3. Two sections higher up. Zt., leaf-trace ; r.,reparatory strand. Section 3 (S. 2946). 
4. Leaf-trace, reparatory strand and adjacent tissues from same section, more 
magnified. px., protoxylem of leaf-trace ; pz.., that of reparatory strand, through 
which a crack passes. x 18. 
5. Two sections above the last. The leaf-trace (/.¢.) shows signs of division, but is 
still slightly connected with the reparatory strand, r. Section 5 (S. 2948). 
6. Four sections above the last. The leaf-trace (/.t.) is evidently dividing iuto two, 
Section 9 (S. 9952). 
7. Four sections above the last, The leaf-trace has now divided into two (lt. Lt.). 
The reparatory strand (».) is still seen behind the trace. Section 13 (S. 2956), 
8. Two sections above the last. The two strands of the leaf-trace (lt, Lt.) are now 
widely separated, with secondary wood between them, and the whole has moved 
considerably further out. Section 15 (S. 2958). 
9. Two sections above the last. The two leaf-trace strands (L4, L/.) have moved 
further apart and each has its own separate fan of secondary wood. The cortex 
is well shown on the left. Section 17 (S. 2960). 
10. Three sections above the last. The two leaf-trace strands (44, Lt.) are now 
passing beyond the wood of the stele. Each is almost or quite surrounded by its 
own zone of secondary wood, Section 20 (3. 2963). 
PLATE 7. 
Calamopitys annularis. 
From photographs (except 14 & 17) by Mr. W. Tams. 14 & 17 by Mr. L. A. Boodle, F.L.S. 
Fig. 11. General section of stele, with part of cortex and leaf-base, containing three 
bundles (v.^.) attached on the left. x 921. Section 40a (Coll. Solms 413). 
12. Stele, from an adjacent section of the same specimen. lt., probable position of 
a leaf-trace. x 3. Section 97, Berlin. 
15. Part of primary and secondary wood, from the same section as Phot. 11. 
lt., probable primary xylem-strand of a leaf-trace. A reparatory strand lies just 
behind. pz., protoxylem of one of the eccentrically mesarch xylem-strands of the 
