LASTREA DILATATA. 



319 



Alta, Moore. — Found at Aberdeen, where it is common. 

 One of the larger forms, with oblong fronds. Robust in habit 

 and erect in growth. Length of frond from forty-eight to 

 sixty inches. Distinctly tripinnate. The pinnules are mostly 

 an inch, and the larger ones two inches in length, and the 

 lobes, which are somewhat distant and oblong, are a quarter of 

 an inch long. The lobes have their tips strongly dentate, and 

 are almost entire towards their base, where they are more or 

 less confluent. This variety somewhat resembles grandidens in 

 the prominent apical dentation. 



Fig. 267— Portion of Frond. 



Decurrens, Moore. (Fig. 267.) — Found near Scarborough, 

 in 1855, by Mr. Clapham. An interesting dwarf monstrosity. 

 Fronds triangular; length twelve inches, of which three inches 

 is the stipes. The usual obliquity of the basal pinnae is not 

 always developed. Pinnae sometimes much abbreviated. Pinnules 

 somewhat distant, narrow, oblong, pointing forwards, and nar- 

 rowed below, the base decurrent; basal lobes usually brief and 

 depauperated. 



Deltoidea, Moore. — Found in Devonshire by the Rev. J. 

 M. Chanter. Length of frond two feet. Fronds deltoid, 

 tripinnate, and finely cut. Stipes slender, with dark scales. 

 Pinnules and lobes blunt, and having conspicuous mucronate 

 unequal teeth. A beautiful light and elegant variety. 



