816 DEPARTMENT OF THE 'INTERIOR 



2 GEORGE V., A. 1912 



1428 

 In the collection of 1905, number-—- comprises a number of linear frag- 



2 



ments devoid of structure or surface markings, though sometimes giving evidence 

 of the presence of vascular bundles in the interior, and rarely showing a some- 

 what carbonized surface. They are always associated with fronds of Gleichenia 

 gilbert-thompsoni, and there is every reason for regarding them as fragments 

 of the stipes of that species. It is also found upon comparison, that they are 

 identical with similar fragments contained in the collections of 1903 and desig- 



. 471 . In the preliminary report upon that material, these specimens 

 nated as,——- 

 1-13 



were referred to as ' representing portions from the rachis of a fern,' but owing 

 to lack of sufficient evidence, regarded as ' essentially of no value for stratigra- 

 pbical purposes.' Close comparison with the remains of C. gilbert-thompsoni, 

 not only confirms this conclusion, but enables us to draw the further inference 

 that they are probably parts of the same plant. 



Specimens 1436 of the 1905 collections, show a single instance of short 

 fragments which are also to be referred in a similar way to some fern of which 

 they are parts of the rachis, and the conclusion is justified that they are identical 



142'S 

 with 471 of 1903, and— of the 1905 collections. 



2 



1430 



Gleichenia. sp. 



2 



A single specimen, under number 1430, shows a fragment of a bipinnate 

 fern frond, which is unquestionably a Gleichenia, conforming to the following 

 description : — 



Pinnae alternate, 5 mm. broad, linear and distant 5 mm. and approximate or 

 slightly overlapping, more than 4-5 cm. long, the apex unknown, uniformly inserted 

 upon the rachie at an angle of 82°; pinnules alternate, ovate, unequal and crowded 

 with the margins somewhat overlapping, the apex round-obtuse, the broad base dis- 

 tinctly rounded, the midrib usually at an angle of 55° with the rachis of the pinna. 



The very imperfectly preserved form of this specimen, and the fact that only 

 one fragment is available, makes the present determination open to some ques- 

 tion, and under these circumstances it does not seem expedient to supply a 

 specific name. So far as it is possible to reach a final conclusion, this plant 

 appears to approximate closely to the European Pecopteris sulziana of Brong- 

 niart (4: pi. 105, f. 4), which differs from it in the shorter and more rounded 

 pinnules attached throughout the full extent of the very broad base, their equal 

 form and an angle of 75°. They resemble one another with respect to the 

 intervals between the pinnae (5 mm.) and in the proximate, slightly overlapping 

 pinnules. It is therefore possible that P. sulziana is the ancestral form of the 

 one now under consideration. 



