80 



LA.CCOPTEEIS. 



the base of each pinna. Sori borne in two rows, on the under 

 surface of the segments, one row on each side of the midrib ; each 

 sorus consists of as many as twelve or fourteen large sporangia 

 (Text-fig. 10), with an oblique annulus and tetrahedral (?) spores. 

 The sori are circular in form, probably without an indusium ; but 

 this point is difficult to decide with certainty, the individual 

 sporangia being attached to a central receptacle as in Matonia, 

 Each segment is traversed by a well-defined midrib, from which 

 numerous secondary veins are given off at a wide angle ; these form 

 a series of elongated areola3 parallel to the midrib, as in the recent 

 genus Woodwardia, and from the areolas or meshes forked and 



FIG. 8. Laccoptcris polypodioides. From a specimen in the York Museum. 

 (f nat. size.) 



anastomosing branches pass off to the border of the segments ; the 

 veins form fairly regularly radiating meshes below each sorus. 

 (Text-fig. 11, and PI. XIII. Fig. 2.) 



Brongniart 1 inclines to the view that the specimens named 

 by Lindley & Hutton Pecopteris propinqua are probably not 

 specifically distinct from P. polypodioides ; an examination of 

 the type-specimen of the former ' species ' in the Scarborough 



Brongniart (28 2 ), p. 374. 



