4 Mededeelingen van ’s Rijks Herbarium Leiden: 
1874, Pl. 6, fig. 3, copied from SrERNBERG’s Volkmannia arbores- 
Cens. C. arborescens Sternb. (non Autt.) 
C. approximatus Roemer, Lethaea palaeoz., 1876, Pl. 50, fig. 3. 
C. schützeiformis waldenburgensis K. 
C. approximatus Heer, Flora foss. Helv.. 1876, Pl. 20, fig. 5. 
Indeterminable. 
C. approximatus Stur, Culmtfl., IL, 1877, Pl. 4, fig. 8. 
C. approximatiformis Stur. 
C. approzimatus Lesq., Coalfl., 1879—80, PL. 1, fig. 5. 
Indeterminable. 
C. cf. approximatus Stur, Morphol. Calam., 1881, fig. 13, 14 and Calam. 
Schatzl. Sch., 1887, fig. 16, 17. 
C. schützeiformis intermedius K. et J. 
C. approximatus Achepohl, Niederrh. Westf. Steink., Erg. Bl II, 
1853 er, Indeterminable. 
C. approximatus Lesquereux, 13th Rept. Geol. Survey Indiana, 1884, 
TBI 5, alen (k C. schützeiformis typicus K. et J. 
C. approximatus Weiss, Steink. Cal., II, 1884, Pl. 25, fig. 1. 
C. schützeiformis waldenburgensis K. 
C. approximatus Stur, Calam. Schatzl. Sch., 1887, Pl. 8, fig. 2, 3; 
Di 2e sl: Indeterminable. 
C. approximatus Stur, Calam. Schatzl. Sch., 1887, Pl. 5, fie. 3; 
Pl. 8, fig. 4. C. schützeiformis waldenburgensis K. 
C. approximatus Stur, Calam. Schatzl. Sch., 1887, PL. 5, fig. 2. 
C. schützeiformis intermedius K. et J. 
C. cf. approrimatus Toula, Die Steink., 1888, Pl. 5, fig 6 (Copied 
from Stur, 1881, 1887). 
C. schützeiformis intermedius K. et J. 
C. typ. approximatus Potonië, Lehrbuch, 1897, p. 191, f. 187 (Copied 
from Srur. 1881, 1887). C. schützeiformis intermedius K. et J. 
C. approximatus Seward, Fossil Plants, 1, 1898, p. 370, fig. 100 
(Copied from Kipsron). C. schützeiformis waldenburgensis K. 
C. approximatus Hofmann und Ryba, Leitptlanzen, 1899, PL. L, 
fig. 5. C. schützeiformis waldenburgensis K. 
C. approximatus Arber, Q. J. G. S., LIX, 1903, PI. 1, fig. 3; Fos- 
sil Plants, 1909, Pl. on p. 53. 
C. schützeiformis waldenburgensis K. 
C. approximatus Renier, Méthodes, 1908, p. 41, fig. 15. 
C. schützeiformis intermedius K. et J. 
C. approximatus Arber, Proce. Yorksh. Geol. Soc., VIL, 1910, p. 
144, Pl. 13, fig. 3. C. schützeiformis intermedius K. et J. 
C. (Calamodendron) approximatus Dawson, Q. J. G. S., XXII, 1866, 
