60 MESOZOIC FLORAS OF UNITED STATES. 



1900. Coniopteris Jiymenophylloides (Brongn.) Sew.: Jiir. Fl. Yorksh. Coast, p. 98, 

 pi. xvi, figs. 4-6; pi. xvii, figs. .3, 6-8; pi. xx, figs. 1, 2; pi. xxi, figs. 1-.3, 

 3a, 4, 4a. 



A small Sphenopteris-like fern, with fructification, was found at 

 locality No. 19. In the shape of its pinnules it much resembles some 

 of the sphenopterid forms from the Lower Oolite of Yorkshire. Seward," 

 in his paper on the plants of the Manchester Museum, gives good rea- 

 sons for adopting the name Coniopteris for some of the sphenopterid 

 forms of the Yorkshire Lower Oolite, and unites a number of them 

 with his species Coniopteris hymenophylloides. In his recent work on 

 the Yorkshire Fossil Plants he gives a number of figures of this species. 

 Some of these agree so well with the Oregon fossil now in question that 

 I have no doubt that it is the same species with the English one. As, 

 however, the amount of material is so small, I do not positively identify 

 it as such. 



The Oregon fossil occurs in only one specimen in counterparts. 

 This shows a small fragment of a penultimate pinna, having several 

 ultimate ones that are nearly entire. The plant is beautifully pre- 

 served. The leaf substance is very thick and it appears wrinkled by 

 the strong nerves and the sori. The ultimate pinnse are verj^ short, 

 the longest being hardly 15 mm. long, while their entire expanse at 

 base, the widest part, is onty about 7 mm. The pinnules are minute, 

 the largest basal ones being not more than about 4 mm. long and a 

 little over 3 mm. wide. They vary a good deal in shape as well as in 

 size, according to their position on the ultimate pinna. The rachis 

 has a narrow wing from which the pinnules rise. On the upper side 

 of the rachis the pinnules are larger than on the lower side. The basal 

 pinnule on the upper side is larger than the others on that side. This 

 larger pinnule is subquadrate in form. The others on the same rachis 

 become more rounded, elliptical, and even club-shaped toward the 

 ends of the pinn*. The pinnules on the lower side are all elliptical, 

 passing to rounded and club-shaped forms. The subquadrate, and 

 indeed all the pinnules, are attached by much narrowed bases. The 

 lateral nerves in the larger pinnules are pinnately, but very obliquely, 

 placed on the midrib. In the others there is a parent nerve. 



« Notes on some Jurassic plants in the Manchester Museum: Manchester Memoirs, Vol. XLIV, No. 8, 

 1900, pp. 5-8. 



