tJ26 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.38. 



form of Leathery, rounded, or elliptical segments, which on the lower side are covered 

 by the naked sori. and seen from the upper side, especially when compressed on the 

 clay, look like pods.« 



The fructification characters should be modified to include those of 

 Acrostichoph ris j>l 'tripartita, which appear to represent entire pinnules 

 reduced to fertile segments and not merely Imsni lobes of otherwise 

 sterile pinnules thus transformed, as appeals to be the case in Acros- 

 tichopteris hngipi /mis. 



With all the collected material at hand it is difficult to see any 

 conclusive evidence that the species included in this genus were 

 creeping in habit or had succulent rachises or that the fertile segments 

 were covered with naked sori. There is some evidence as to fructifi- 

 cation characters, but this is most indefinite as regards details, and 

 it may be noted that what are called nut-like seeds when applied to 

 fragments referred by this author to his genus Baieropsis are described 

 as above for fragments which he referred to the present genus, 

 although neither the fertile nor the vegetative parts are distinguish- 

 able with certainty in these two supposed genera. 



All of the species which constituted the genus Baieropsis of Fon- 

 taine, except Baieropsis (.rjxntsa and Baieropsis macrophyUa are 

 referred to Acrostichopteris in the present paper, with which they are 

 obviously allied in instances where they are not actually identical. 

 They presenl no characters which are clearly those of the order 

 Ginkgoales except their subdivided fronds, which are suggestive of 

 Baiera or Jeanpaulia, but might equally suggest various living 

 Polypodiaceae, as, for- instance, Actinopteris and RMpidopteris or the 

 various species of Scliizxa of the family Schizaeaceae. Among fossil 

 species they are very similar to forms referred to Sphenopteris, Pal- 

 matopteris, etc. Considerations which point away from Baiera in 

 the direction of the ferns are the fine inequilateral outline of t lit* 

 leaves (pinnules), their decurrence, and their arrangement in a 

 pinnate manner in a single plane. The two species Baiera j>s Is <spansa 

 and macrophyUa furnish fructified specimens which clearly indicate 

 their reference to the family Schizseacese. These will be fully dis- 

 cussed in another place. 



With regard to the botanical position of Acrostichopteris little is 

 known. According t<> Fontaine: 



The genus in the naked sori is like Polypodium, but in mosl Features stands nearer! 

 to Acrostichum, much resembling the section Rhipidopteris. In this latter, however, 



the fructification is bon a separate pinnules. If we place the fructified pinnules of 



Rhipidopteris as basal segments on the sterile one-, we have a form strikingly like 

 Acrostichopteris. This genus has also some reseinlilai.ee to Marsilea. 



Seward b on the strength of Fontaine'- conclusions as quoted above 

 places the genus in the Polypodiaceae, and the present writer in the 



fflfonogr. U. S. Geol. Surv., No. 15, 1890, p. 106. 

 b Seward, Wealden Flora, pt. 1, 1894, p. GO. 



