XXXIX] NILSSONIA 573 



face of the segments and between each pair is a single unbranched 

 vein. In close association with portions of three fronds of this 

 species Nathorst found several oval bodies, 1 cm. x 7 mm., 

 which he at first regarded as ' antherangia ' comparable with the 

 sporocarps of the Hydropterideae, but an examination of the 

 carbonised tissue demonstrated that the small rounded bodies 

 contained in each of the ' antherangia,' originally believed to be 

 pollen-sacs, are grains of resin internal to a cuticle of thick-walled 

 cells and probably formed by secretory sacs in a fleshy tissue. 

 Internal to the resin-bodies is a second cuticle which may be the 

 remains of a nucellus, the outer cuticle and the resin belonging 

 to the sarcotesta. Nathorst's careful examination of these fossils 

 shows that they are seeds (fig. 619, A) and were probably borne 

 on plants of N. pterophylloides, though an accidental association 

 is not improbable. 



Nilssonia compta (Phillips). 



Broadly linear fronds varying considerably in size and in the 

 breadth and number of the truncate segments. In some cases 

 the fronds exceeded 40 cm. in length and had a breadth of 9 cm. 

 (fig. 622). The veins are simple, parallel, and fairly prominent 

 and the lamina shows clearly the attachment to the upper surface 

 of the rachis which is covered by it as in all species of the genus 1 . 

 The structure of the epidermis and stomata has recently been 

 described by Thomas 2 . Brongniart mentioned in the Prodrome 

 a species from the Lower Oolite of Yorkshire under the name 

 Pterophyllum Williamsonis 3 , but in a later work this is given as a 

 synonym of N. compta. Nilssonia compta bears a close resemblance 

 in habit to N. polymorpha', it agrees also with the large fronds 

 described from the Upper Gondwana of India as Pterophyllum 

 princeps*. Since attention was first called to this similarity an 

 examination of several of the figured specimens has convinced 

 me that the Indian fronds are either identical with or at least 



1 Phillips (29) A. p. 148, PL vn. fig. 20. See Seward (00) B, p. 223, PI iv. fig. 5 ; 

 text figs. 39, 40. 



2 Thomas and Bancroft (13) p. 191. 



3 A specimen in the Natural History Museum, Paris, labelled N. Williamsonis 

 i* probably that mentioned by Brongniart. 



4 Oldham and Morris (63) B. Pis. x. xm. ; Feistmantel (77) PI. XLVII. 



