XXXIl] 



METAXYA 



29.1 



uprio-ht pose: but the underlying scheme of them all is the same. The 

 vascular anatomy accordingly remains primitive also, as well as the dermal 

 appendages. The fertile pinnae and sori, however, are advanced. The 

 former have resulted from a condensation of more elaborate branchmg mto 

 broad simple pinnae, though relics of a more elaborate structure are still 





o><ry^u, 



Fig :^S4- Tangential section through part of a young 

 torus of A/eiaxya rosirata, showing the hairs and 

 sporangial stalks cut transversely. The stalks consist 

 each of four cell-rows and are orientated with 

 regularity. ( x 250.) 



Fi'a- s=;s Illustrations of the two-rowed segmentation of Pern sporangia. 

 %. I, young sporangia of Cheiropleuria. showing aspects at right-angles to 

 one another. ( x 165.) c, d, similar drawings oi Metaxya ( x 200.) ., is 

 a rather older sporangium of Melaxya seen from above : /, seen from the 

 side. /?,/i = hairs. ( x 200.) 



seen in the marginal serrations, indicating the pinnules which are webbed 

 to form the wider expanse. But it is in the sori and sporangia that Metaxya 

 shows its most advanced features. The mechanical dead-lock of G.pectmata 

 has been resolved along three lines of advance. The receptacle is not 

 elono-ated, as in the Gradatae, but remains about the same height as m 

 ^ 19-2 



