NO. 2151. FOSSIL PLANTS FROM FLORISSANT— KNOWLTON. 287 



This form was referred to the genus Porana of the Convolvrilaceae, 

 by Lesquereux on the ground of its undoubted resemblance to cer- 

 tain European Miocene forms, such as Porana micrantha Ludwig, 

 P. oeningensis (Al. Braun) Heer, etc., in some of which, but especially 

 the last-mentioned species, the characteristic fruit has been obtamed. 

 Up to the present time, so far as known to the writer, no American 

 specimen has been recorded which has the fruit preserved, which 

 would prove absolutely the correctness of the generic reference. It is 

 with great pleasure, therefore, that I am able to state that two splen- 

 didly preserved specimens in the Hambach collection supply this 

 missing character. As may be seen from the figures (pi. 27, figs. 

 4, 5), the sepals are identical in number, shape, size, and nervation 

 wilh Porana tenuis, and in addition each has the globular capsule 

 preserved in situ. The capsule is about 7 mm. in long, and 6 mm. in 

 short diameter, and was evidently very firm and of considerable 

 strength since the depression in the matrix is fully 1 mm. deep. In 

 one of the specimens (pi. 24, fig. 5) there is some evidence of the 

 presence of seeds, but this may be only an accident of preservation. 



This species is, of course, entirely distinct from Porana speirii 

 Lesquereux, and P. similis Knowlton, being approached only by P. 

 cockerelli, the description of which follows. 



PORANA COCKERELLI. new species. 



Plate 27, fig. 3. 



Porana tenuis Lesquereux. Cockerell, Bull. Amer. Mus. Nat. Hist., vol. 

 24, 1908, p. 107, pi. 6, fig. 10. 



Similar to P. tenuis, but with the sepals shorter, obovate instead of 

 oblong, and with the apicies much more obtuse and rounded ; cap- 

 sule oblong, roimded at apex. 



Type— Cd^t. No. 34,747, U.S.N.M. 



The sepals are about 13 mm. long and about 6 mm, wide at the 

 broadest point which is near the apex. They are distinctly obovate 

 in shape and nearly or perhaps quite free at base. The nervation is 

 very distinct, consisting of about 5 veins which arise at the base, 

 about 5 mm. apart, and with one or two branches above. The finer 

 nervation, if present, is now obsolete. The size and character of the 

 capsule is weU shown in the figure. 



This species is so very closely related to P. tenuis that it is perhaps 

 with doubtful propriety that it is held as distinct from it. It differs 

 from P. tenuis as above indicated by its slightly smaller size, and 

 obovate, very obtuse sepals. 



This form is undoubtedly the same as the example figured by Cock- 

 erell under the name of Porana tenuis, and by a curious coincidence, 

 which may be with or without significance, each of these specimens 

 has only four sepals as at present preserved. The natural inference 



