288 Berry: A NEW MATONIDIUM FROM COLORADO 
an original feature or is due to collapse during fossilization is 
undeterminable. Distad the stipe expands into a flabellate 
recurved or reflexed ‘‘collar’’ which shortly divides to form the 
axes of the pinnae, whose attitude in life was transverse or re- 
flexed with respect to that of the vertical stipe. These reflexed 
collars’’ are especially common in the rocks and are the objects 
which Cockerell referred to Cycadospadix. They are well shown 
in PLATE 12, FIGS. 9-I2. 
The width of the “collar” before it split up into pinnae varies 
from specimen to specimen and is not always clear, although it is 
narrowest medianly. No traces of pinnules have been found in 
actual connection with these stipes although they are in close 
association. The divisions of the ‘‘collars,’’ however, do not 
terminate as they would if the fossils were of the nature of Cyca- 
dospadix, and the breaks at the ends are obviously mechanical 
and not natural. The evidence of their reflexed form is also 
clear, and the size of the segments, their condition of preser- 
vation and furrowing are in exact agreement with the speci- 
mens of proximal pinnae axes. The number of pinnae was large 
but somewhat variable. The ‘‘collar’” shown in Fic. 9. indi- 
cates four lateral pinnae at each end of the collar and thirty- 
one additional intercalated pinnae, making thirty-nine in all. 
Fic. 10 shows clear traces of at least twenty-five pinnae, and 
Fic. 12, which is the counterpart of the apex of the specimen 
shown in Fic. 11, shows the bases of thirty-six pinnae. The 
pinnae were therefore much more numerous than the published 
figures indicate for Matonidium Althausii and also somewhat more 
numerous than the normal number in the modern Matonia pecti- 
naia. The exact length of the pinnae is unknown since all are 
preserved in a fragmentary condition, but judging by the frag- 
ments of proximal, medial and distal parts preserved, and the 
size and degree of tapering of the rachises, they could not well 
have been shorter than 20-25 cm., or about the same length as in 
the admirable specimen of Matonidium Alihausii figured by 
Schenk* from the German Wealden. Their width, however, was 
much less than in that species, the largest certainly identified 
(PLATE 12, FIG. 8) being but 11 mm. across, while the more abund- 
* Palaeont. 19: pl. 28, f. 1. 1871. | 




