FLORA OF THE SHASTA FORMATION. 253 



1894. Nilsonia pterophylloides Y ok. [non Nath."]: Jour. Coll. Sci. Imp. Univ. Japan, 



Vol. VII, Pt. Ill, p. 228, pi. xxii, figs. 8-10; pi. xxv, fig. 7. 

 1895 [1896.] Pterophyllum californicum Font, in Stanton: Bull. U. S. Geol. Surv., 

 No. 133, p. 17. 

 A single specimen of a cycad was found at localitj^ No. 14, which 

 appears identical with the plant named Nilsonia pterophylloides by 

 Yokoyama, from strata of Neocomian age in Japan. The California 

 specimen, depicted in Fig. 44, is a fragment of a leaf 45 mm. long, which 

 bears a number of segments, some of which are entire and which are 

 pretty well preserved. The segments have approximately the same 

 shape as those of Yokoyama's plant. The nerves are about 10 in number, 

 single and parallel. The specimen looks a good deal like a PterophyUum, 

 as it has suffered somewhat from maceration, which has removed the 

 epidermis of the midrib, but careful inspection shows that the bases of 

 some of the segments are still preserved and that they pass over the 

 margin of the midrib to meet in its center, as in Nilsonia. The segments 

 are not quite so uniform in width as those of the Japanese plant, some 

 being slightly wider than others, but not markedly so. The length of the 

 segments is 15 mm. and their average width is about 6 mm. The form 

 is clearly one not hitherto found in the Lower Cretaceous of North America 

 and it is so near that of Yokoyama's plant that it seems identical. Besides 

 this, the Japanese beds have yielded a number of others identical with 

 forms from the Lower Cretaceous of North America. 



and rounded. The nerves are distinct, closely placed, and in the average leaflets 8 in number, but are more 

 numerous in the wider leaflets, which may be half as wide again as the average ones. 



" This Pterophyllum resembles in some points both of the species with which I have compared it, and appar- 

 ently it is a connecting link between them. Probably all three of these plants are varieties of one species. Its 

 general appearance is much like that of P. concinnum, so far as the shape and size of the leaflets go, but they 

 are somewhat wider in proportion to their length. The main difference is in the varying width of the leaflets 

 and the greater number of nerves. Heer's plant has commonly only 4 nerves, and at most only 6, and the 

 leaflets are very uniform in width. It is very near to P. Brongniarti, differing from it only in the shorter leaflets. 

 P. Brongniarti shows the same nervation and variability in the width of the leaflets. The plant now in question, 

 in the form of its leaflets, looks something like Zamites montansnsis , which I described from the Great Falls 

 flora, but is clearly quite different from that." — L. F. W. 



" See footnote to p. 96. Professor Fontaine in his final report identified this plant with that of 

 Yokoyama, but as Yokoyama's name was preoccupied that of Professor Fontaine becomes the name of the 

 species. Though published the same year it must have antedated Yokoyama's name by several months, but 

 as Diller and Stanton did not publish Professor Fontaine's description, which they had before them, his name 

 would have had to give way to Yokoyama's if that had not been preoccupied.. As it is, Fontaine's name may 

 remain, and as he now refers the plant to the genus Nilsonia, the above combination is virtually his.— L. F. W. 



