MATONINEAE 



565 



to hold a terminal position, has been recognised as the inner branch of 

 the second dichotomy. The segments themselves are pinnatifid, and the 

 solitary sori are borne on their wings at points near to the midrib. The 

 other species, M. sarmentosa, grows on rocks or on the branches of trees, 

 with straggling, pendent leaves : at first sight the branching of the leaf 

 seems quite different from that of M. pectinata ; but this is due partly to 

 the unequal development of the dichotomies, certain of the branches being 

 represented only by arrested buds : partly it is due to their sympodial 

 concatenation : but still the dichotomous branching appears to hold for 



FIG. 315. 



Matonia pectinata, R. Br. Leaf drawn from a specimen in the British Museum 

 Herbarium, by Mrs. Seward. natural size. 



Doth. An interesting feature in this species is that the sori are borne in 

 arger numbers, forming a row on either side of the distal part of the 

 Dinnule : an arrangement more closely resembling that in Gleichenia than 

 hat of M. pectinata. The , structure of the sorus is, however, precisely 

 ike that in M. pecti?iata^ and there is no doubt of the close alliance of 

 he two species. 



SPORE-PRODUCING MEMBERS. 



The general structure of the mature sorus is well known ; the sporangia, 

 commonly six to nine in number, form a simple ring-like series round the 

 receptacle, and are covered till maturity by the thick and leathery hemi- 

 spherical indusium, which is ultimately deciduous* The orientation of 

 the sporangia is not exactly uniform ; that of the majority is as in Gleichenia, 

 3ut many have the annulus inclined, a consequence probably of crowding ; 

 this is seen also in the fossil Laccopteris. The annulus is incomplete at 



