CONIOPIERIS. 109* 



-PI- XVII. Tie apices of the pinnae shown in Eig. 1 are identical 

 with those of Fig. 2, and the less deeply cut and rather broader- 

 pinnules in Fig. 2 are connected with the more deeply cut 

 segments of Fig. I by transitional forms met with here and there. 

 I have no hesitation in regarding the fi-onds of Figs. I and 2 as 

 those of one plant, or at least of one species. That shown in 

 Fig. I is identical with Heer's Thyrsopteris MaaUana, hut it is 

 connected, by slightly larger forms, with ;S'. hymenophylloides,. 

 Brongn., and with S. arguta, L. & H. ; the fi-ond of Fig. 2 

 agrees exactly with some of the published figures of S. Mwrayana, 

 S. affinis, PhiU., and other 'species.' The difference between 

 Figs. 1 and 2 is far less than one finds between fronds on the 

 same plant of several recent ferns. 

 Cf. Scleropteris tenuisecta, Sap.' 



39,261. PI. XXI. Fig. 1. 



This specimen illustrates a further poiat confirmatory of the- 

 specific identity of the fronds with sharper and longer pinnules 

 with those bearing the more rounded and shorter segments. In this 

 pinna the segments are of the former type, as in S. hymenophylloides, 

 Brongn. ; but at the base of the pinna the two lowest pinnules- 

 are curiously modified and have a form suggestive of an Aphlehia- 

 type of lamina, the lamina being much more deeply cleft and 

 the narrow linear divisions much longer and more spreading. 

 Exactly similar Aphlelia-^ke segments are met with on pinnsB 

 bearing the shorter and more rounded pinnules. 



Cf. Sphenopteris minutula, Sap.^ 



Scarborough. Bean Coll. 



52,597. PL XXI. Fig. 2. 



This pinna is of the same type as those shown in PI. XVI. 

 Fig. 6 and in PI. XX. Fig. 2. The lowest pinnule on the left- 

 hand side exhibits a long branched segment like the Aphlebia 

 form in the preceding specimen (PI. XXI. Fig. 1). 



' Saporta (91), pi. Ixi. 



' Ibid. pi. Ivi. Cf. also Alloiopteris quenifolia (Goepp.), as figured by- 

 Potonie (99), p. 139. 



