THE ANATOMY OF TODEA. 253 
| Geological | Geographical 
CHEM horizon. | distribution. 
Doe t auc LU UL E vein NIS eer epi Ex IUE UHR, iw 
| JTodues Wiliamsont |... M S | Jurassic. | England. 
| Acrostichites linneefolia, Rog. ........... Beien | Rheetic. | N. America ( Virginia). 
| 4E rhombifolius, Font. 155.5 on Ae ae » | j) 5 
| Tudea Williamsoni* : 7, 15 A | Jurassic. | Poland. 
| Acrostichites Goeppertianus (Muenst.) ? ............ Rhetic. | Germany. 
| de E, - |! Scandinavia, 
| 5 Wiliamsoni Tee dE e | Persia. 
» 3.5.0 s. BREL i eco ip UN Jurassic. | Russia, 
| Pecopteris whitbiensis, Brongn.’ ..................... | China. 
Pfleeg Wilkamsoni* ZE » | Greenland, 
| Asplenium whitbiense" cana a S | Siberia. 
| Dichopteris microphylla, Zeng"... a Italy. 
Maplenium whitbiense* Si AIR BR 8 | Japan. 
Cladophlebis virginiensis, Font," Tae oae Add gp N. America. 
` Fontaine (1883). ? Raciborski (1894). ? ' Schenk (1867), Soe: & 6. 
* Eichwald (1866), pl. 2. fig. 3. * Schenk (1883). * Hartz (1896), pl. 12. " Heer (1877). 
* Zigno (1856), pl. 15. fig. 5. * Yokoyama (1889), pl. 2. fig. 3. ? Fontaine (1889), pl. 3. 
Altention has elsewhere * been drawn to the confusion that exists in pal:obotanical 
literature between the true Zodites and several of the bipinnate fronds described under 
such names as Pecopleris whilbiensis, &c. The specimens described by Brongniart in 
1828 as Pecopteris denticulata, and now referred to the genus Cladophilebis, may be 
taken as typical of a form of a fern-frond very widely spread in Mesozoic floras. 
Without entering further into the question of synonymy, we would draw attention to 
the occasional occurrence of fertile pinnæ (Pl. 27. fig. 4) which there is good reason 
to believe belong to Cladophlebis denticulata. This species has been doubtfully referred 
to the Polypodiaceze +, but in the absence of well-preserved sporangia its systematic 
position must remain doubtful; on the other hand, the resemblance between the fossil 
specimen shown in fig. 4 and the fertile pinne of Todea barbara suggests the possibility 
that Cladophlebis denticulata may possibly be another Jurassic member of the 
Osmundacez. While agreeing closely in form with Todites Wiliiamsoni, the fronds of 
Cladophlebis denticulata may usually be recognized by the longer and more falcate 
pinnules, which may have an entire or denticulate margin. The variation in the character 
of the ultimate segments of Todea barbara (Pl. 27. figs. 2, 3, 4) finds a parallel among 
the Mesozoic types. We do not for a moment suggest that the superficial resemblance 
between the fertile pinne of the fossil fern with those of Todea barbara (ef. Pl. 27. 
figs. 2 & 4) constitutes a valid argument in favour of an Osmundaceous affinity, but it 
would seem to be at least as likely that Cladophlebis denticulata may be a member of 
the Osmundacez as of the Polypodiace:e. 
: * Seward (1900), p. 89. + Seward (1900), p. 143, pl. 20. figs. 3 a, 3 b. 
SECOND SERIES.—BOTANY, VOL. VI. 20. 
