264 BAIEKA. 



less blunt point. The breadth and number of the segments vary 

 considerably in different leaves. 



The plant to which. Bunbury gave the name Baiera gracilis had 

 previously been named by Bean ScM%opteris gracilis, but the 

 latter term was never published, and is quoted, therefore, as 

 a manuscript name. Bunbury compares his species with Cyclopteris 

 Suttoni, Sternb. (= Ginkgo), and sees no reason for removing these 

 two species from the ferns ; he quotes Acrostichum peltatmn as 

 a recent fern of similar habit. The leaves of Baiera gracilis differ 

 but little from some of those usually referred to Oinkgo Muttoni, 

 Baiera longifolia or B. Pliillipsi, and Solenites furcatus ; all exhibit 

 the same general form, and are characterized by forked segments ; 

 in B. gracilis the segments are linear and narrower than in. 

 G. Suttoni, but broader than in the plant we have named 

 B. Lindleyana. 



Some of the Siberian leaves figured by Heer as Ginkgo lepida'^ 

 are indistinguishable from Baiera gracilis ; Heer's Greenland 

 species, Baiera incurvata' and B. CzehanowsMana,' may also be 

 compared with B. gracilis. A fragment described by Fontaine 

 from the Potomac beds as Baiera foliosa * bears a resemblance to 

 Bunbury's species, and a specimen fig-ured by Schenk from China 

 as B. angustiloha ^ is also not unlike the English type. 



Some specimens of Bunbury's species appeal' to be identical with 

 the Ehsetic species Baiera (or Jeanpaulia) Muensteriana (Presl).* 

 This probable identity, or at least striking resemblance, is 

 illustrated by specimen 39,209 (PL IX. Fig. 3), which may be 

 referred to as B. gracilis, forma Muensteriana. 



The form of leaf represented by Baiera gracilis, Bunb., is one 

 which was very widely distributed in Mesozoic times ; in addition 

 to the species already mentioned as possibly identical with this 

 type, several others might be quoted, but in most cases the data 

 are insufiicient to enable us to do more than call attention to 

 resemblances without necessarily implying specific identity. It is 



' Heer (80), vol. vi. (2), pi. v. fig. 3a. 



"• Heer (80), vol. vi. (3), pi. xiii. fig. 6. 



s Heer (80), vol. vi. (2), pi. ii. figs. 1-3. 



* Fontaine (89), pi. xciv. fig. 13. 



<■ Schenk (83), pi. liii. fig. 1. 



« Schenk (67), pi. ix. 



