90 FLORA OF LOWER COAL MEASURES OP MISSOURI. 



As I was somewhat uncertain as to the g-eneric reference of the fertile 

 pinnae, a few fragments were sent to Prof. E,. Zeiller, who is preeminently 

 experienced in the determination of carbonized fertile Paleozoic ferns. 

 This distinguished author, who has had the kindness to examine these frag- 

 ments, writes that he considers them as somewhat intermediate between 

 Asterotheca and Scolecopteris, though probably much nearer the Asterotheca 

 type, especially as that is seen in Pecopteris (^Asterotheca) hemitelioides 

 Brongn. My own observations lead me to accept Professor Zeiller's con- 

 clusion, for the sporangia appear to me to be attached by the base, without 

 IDedicels, while at the same time they are larger, broader, and less acute 

 than in any described species of Scolecopteris. They appear in part con- 

 siderably like the figure given by Stur^ as Hawlea Miltoni. It is hoped 

 that additional details may be brought out in future in the course of a more 

 leisurely study of this and other fertile species in this flora. 



The original (No. 3173 of the Lacoe collection) of fig. 5 on pi. xlii of 

 the Coal Flora, described as the fruit of Pecopteris clintoni, appears to me 

 to be indistinguishable from the fertile pinnse of Pecopteris psemlovestita seen 

 in many fragments from Pitcher's coal bank. The oval bodies delineated 

 as sporangia are the protuberances of the upper surface of the slightly 

 macerated lamina over the sori. The sporangia themselves appear to belong 

 to the type described above. It should be noted that the fertile pinnules 

 do not taper as much as represented in the artist's drawing, nor are the 

 sterile pinnules above so broad and compact. Very good examples of the 

 fertile pinnge of our species are seen in Nos. 3142 and 3127, labeled P. 

 vestita, of the Lacoe collection, while 3140 is typical of P. pseiidovestita. 

 However, in No. 3097 of the Lacoe collection, mentioned above, we have 

 a well-preserved segment labeled Alethopteris ambigua in which a portion is 

 fertile, the sporangia being expressed on the iipper surface of the lamina. 

 Several other fossil specimens, also labeled Alethopteris amhigua, agree in all 

 respects with the fertile pinnae of our species and should be referred 

 thereto. 



Among the Old World species, Pecopteris pseiidovestita is perhaps most 

 similar to the smallest pinnae of P. ahhreviata Brongn. In the latter species, 

 however, the corresponding parts are very much lai'ger and the pinnae much 

 more oblique, while the nervation is not so dense. From P. oreopteridia 



'Fame A. Carbon-Fl., p. 106, figs. 17J-C. 



