128 FLORA OF LOWER COAL MEASURES OF MISSOURI. 



the new evidence derived from the morphologic observations tends to con- 

 firm the intimate relations of the g-enus Neuropteris to Linopteris,^ Odontop- 

 teris, and CaUipteridmm, while the structure seems to confirm their inclusion 

 among the synthetic forms with highly organized petioles having some 

 characters intermediate between the ferns and the cycads. 



The opinion advanced by the late Director Stur, that Neuropteris may 

 belono- to the Cycadese, is briefly reviewed by Seward" in his admirable 

 volume on the Mesozoic Cycads, without admission of the evidence on either 

 side of the question as conclusive. It is true, as Seward points out, that 

 the specimen regarded by Kidston^ as a fertile fragment of Neuropteris hete- 

 rophylla Brongn. seems hardly to furnish all the characters for a satisfactory 

 conclusion. I have seen similar fruiting. fragments from the Coal Measures 

 of West Virginia with rediiced pinnules, probably of an Adiantitoid type, 

 still attached. On the other hand, the oblong intemeural pits with slightly 

 raised Ijorders, described by various authors as the fruit of this genus, are 

 now generally admitted to be the work of fungi. They might be compared 

 with Hysterites, or even, as Stur suggested, with the recent Phyllaclwra. If, 

 however, we accept Zeiller's identification of certain fertile pinnae in the 

 Commentry flora* as belonging with the sterile forms of Linopteris ScMtzei 

 (Roem.), the fruit of a typical species of Linopteris {Biciyopteris) bears a 

 strong superficial resemblance to that of Pecopteris polymorpha, i. e., to 

 Scolecopteris. Neuropteris and Linopteris are among the .most closely related 

 of the artificial genera in the Paleozoic flora, the anastomosis of the nerves 

 constituting the only distinction between the latter and the group repre- 

 sented by 'Neuropteris gigantea Stb. 



In ray earlier discussion of the relations of Tceniopteris missouriensis I 

 urged the genetic relation of Neuropteris, Dictyopteris, Odontopteris, Callip- 

 teridium, and the pinnate Tseniopterids from the same type as the Devonian 

 Megalopteris, designating this early ancestry as the " megalopteris stock."" 

 The superficial characters of certain material subsequently examined tends 

 strongly to support this view. But at the same time I should expressly 

 state that the Megalopteris forms as yet discovered can not be so ancient as 



' Diclyopteris Gutb. 



-Cat. Mesozoic Foss. PI. Brit. Mus., pt. 2, 1895, p. 5. 



^Traus. Roy. Soc. Edinb., vol. xxxiii, 1887, p. 150, pi. viii, fig. 7. 



■• Fl. foss. houill. Commentry, vol. i, 1888, p. 273, Atlas, pi. xxx, figs. G-10 ; pi. xxxi, figs. 2-5. 



■■ Bull. Geol Soc. Amer., vol. iv, 1893, pp. 119-132, pi. i. 



