m 



I'DlASTIC'IiUM AKGULAKE. 



Fig. 150.— Middle pinna, and basal pinna. 



Trifinnato-becompositum, Loioe. (Fig. 150.) — Found near 

 Nettleconibe by Mr. Charles Elwortliy, and named by him 

 Iripinnatum, from its truly tripinnate character; it is, however, 

 a very distinct form of Decompositum. Length above three 

 feet, width nine inches; colour rich green; lanceolate and 

 tripinnate. Pinnw opposite on lower half of frond, alternate 

 above, lanceolate, distant in the four basal pairs of pinna.^, 

 the next ten pairs approximate, and the remainder crowded. 

 Pinnules in the basal tlirce or four pairs of pinnte much 

 broader than those higher up the frond, distinctly auriculate; the 

 inferior pinnules longer than the superior ones, but the basal 

 pinnnles, both superior and inferior, less than the others, 

 distinctly stalked, except near the apex, and the auricle pro- 

 foundly divided. In the centre of the frond the pinnules 

 are much more deeply divided, the superior basal pinnule is 

 lanceolate, an inch long, (nearly twice the length of the others,) 

 has a large auriculate stalked lobe, and the half dozen lower 

 pairs of lobes all stalked; the other pinnules in the basid 



