Bound — Crossotheca from R. I. Carboniferous. 133 



According to Kidston, 3 Crossotheca fruits are not, as 

 formerly supposed, the exannulate fertile pinnae of Pter- 

 idophytes allied to the Marattiaceae but represent micro- 

 sporangiate parts of a Pteridosperm, the sterile forms of 

 which are of the Sphenopterid or Pecopterid type. 



Fig. 3. — Showing specimen as figured by Gutbier. 



Three typical Crossotheca species from the European 

 coal flora show noteworthy differences from the American 

 form. Crossotheca schatzlarensis Stur 4 consists of a 

 more complex panicle than the Rhode Island specimen, 

 the units of which are divided into four to eight antheridia 

 as contrasted with fifteen to twenty in Crossotheca nana. 

 The size of each unit, however, is about the same as that 

 of the Rhode Island form although the proportions are 

 very different, being loose where Crossotheca nana is 

 compact. Sphenopteris (Crossotheca) Crepini Zeiller 5 

 is about the size of the Rhode Island species but more 

 stout in form and simple in details. Sphenopteris (Cros- 



3 Kidston, E. : Phil. Trans. Eoy. Soc, vol. 198B, pp. 413-445, Pis. 25-28, 

 1908. Les vegetaux houillers recueillis dans le Hainaut beige, p. 41, 1909. 



4 Kidston, K. : Proc. Eoy. Phys. Soc, vol. 9, Pi. 21, figs. 1-6, 1888. 



5 Zeiller, E. : Bassin houiller de A r alenciennes, PI. 13, figs. 1-3, 1886. 



