524 INTKODUCTION TO CRYPTOGAMIC BOTANY. 



and variously lobed and crisped. These organs, as appears 

 from the observations of De Vriese and my own examination, are 

 very sparingly supplied with vascular tissue. The rhizoma is 

 generally a large globose mass, rough with the processes from 

 which the stipes have fallen. It sends out a few large aerial 

 roots, and consists of loose cellular tissue abounding in starch, 

 and small scattered bundles of vessels. In many Marattiacece, 

 as, for example, ■ in Angiopteris evecta, the surface of the 

 stipites and the appendages is sprinkled with pale linear 

 patches, which have been compared to the lenticelles of Phse- 

 nogams. It has been said that several layers of cells shell off 

 from these patches. The surface, however, is quite continuous 

 with that of the rest of the stipe or its appendages, and in the 

 dry stipe lines of the pale tissue radiate from these spots into 

 the surrounding parenchym. The absence of colour depends 

 upon the nature of the endochrome of the cells. It may be 

 remarked that in Vriese's book the species are multiplied be- 

 yond any reasonable bounds, a fact which everyone will aUow 

 who has had an opportunity of examining a really good series 

 of specimens. 



591. It was said that the sporangia in this tribe are more or 

 less confluent. In Angiopteris they are less so than the other 

 genera, being confluent only at the very base. The sori are 

 seated towards the tips of the veins, and the sporangia, which 

 are obovate and burst longitudinally, are disposed in a row on 

 each side of a little linear receptacle projecting from the vein, 

 so as to form a narrow ellipse (Fig. 117, a). Marattia has 

 "the sori at the ends of the veins just within the margin; 

 each consists of two opposite parallel plates, with convex backs 

 and plane faces, the latter marked by vertical gashes, opening 

 into as many cells containing spores." The two rows of spo- 

 rangia are at first combined into a common solid mass, but 

 this, after a time, splits in the direction of the vein, and 

 becomes bivalvate. Eupodium is distinguished from Marattia 

 by the narrow indusium, which was sessile in that genus, being 

 pedicellate. In Danwa the two rows are intimately combined 

 with cellular tissue into a chambered mass, each chamber 

 containing two sporangia, and the spores are discharged by 



