BY DR. B. CARRIXGTON AND \V. II. PEARSON. 1041 



16 IsoTACHis GuNNiANA, Mitt., Fl. TasiB., p. 232. 



On rocks, Mermaid's Glen, Blue Mts., Sept., 1885 (12). 



17 ISOTACHIS GRANDIS, Xl. Sp. 



Laxly caespitose, large, rosy brown ; stems simple, rai'ely 

 branched ; leaves distichous, closely imbricated, sub-complicate, 

 rotundo-ovate, bitid to about l-4th, sinus and segments subacute, 

 often trilid, margin entire or with few teeth near the base, texture 

 thin, cells elongate ; underleaves smaller, elliptic-ovate, bidentate 

 to l-3rd, entire or sparsely dentate. 



Growing in loose patches of a rosy brown colour. Stems long, 

 flexuose, brown, simple, rarely branched. Leaves distichous, 

 closely imbricated, patent, amplexicaul, sub-complicate, ventricose 

 at the base, rotundo-ovate, bifid to about l-4th, sinus and seg- 

 ments sub-acute, postical segment often again shallowly bitid, 

 margin entire or armed with one or two teeth near the lower half ; 

 texture thin but firm,, slightly polished, cells rather large, rhom- 

 boidal, 2-3 times longer than broad ; walls firm, without trigones. 

 Underleaves smaller than the leaves, plane or more or less convex, 

 elliptic-ovate, bidentate to l-3rd, sinus obtuse or acute, seg- 

 ments acute, margin entire or armed with a few irregular teeth. 



Measitrements. — Stems from 3 to 4 inches, 3* mm. wide ; leaves 

 •3 mm. diam., leaves 1-75 mm. long x 1*5 mm, broad; segments 

 -5 mm.; cells '07 mm. x -025 mm.; underleaves 1*5 mm. 

 long xl' mm broad; seg. "5 mm., rarely l'75mm. long xl* mm. 

 broad ; seg. '35 mm. 



Hab. — On wet rocks, Lawson, Blue Mountains, June, 1884. 



Obs. — This large and beautiful species has only been found 

 sterile, yet it is so different from any of the described species that 

 we do not hesitate to consider it a new species. 



Isotachis suh-trifidus (H. f. et T.) lias longer, narrower leaves, 

 with the apices equally ti-ifid. 



The generic characters of Isotachis, as given in the " New Zea- 

 land Flora," are very meagre and imperfect. 



