80 



LACCOPTEEIS. 



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

 surface of tbe 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 areolae parallel to the midrib, as in the recent 

 genus Wbodwwrdia, and from the areolae or meshes forked and 



Fig. 8. — Laccopteris 



From a specimen in the York Museum. 

 (J 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. Eig. 2.) 



Brongniart ' 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'), p. 374. 



