Colenso. — On the Feins of New Zealand. 215 



Obs. This species has a pleasing appearance living, from 

 the graceful airiness and softness and light-green colour of its 

 rather small fronds, reminding the beholder, at first sight, of 

 another arborescent fern of those forests, Hemitelia smitlui, 

 Hook. fil. (Like some other of our ferns it, unfortunately, loses 

 its pleasing green colour in drying.) It approaches D. fibrosa, 

 Col., more nearly than it does I), squamosa, Swartz ; but it is 

 still more nearly allied to D. sparmanniana, Col.,* and to D. 

 gracilis, Col.,1 differing however from both in its smaller and 

 much narrower fronds and segments, and also from D. sparman- 

 niana in being arborescent, and in its very small sori and 

 involucres ; and from D. gracilis in the great difference in its 

 caudex, and in its veins, sori, and involucres being scarcely half 

 the number of those of that species on a segment, as well as in 

 several other particulars. Hitherto I have not met with many 

 plants of this species in the forests. 



Genus 11. Adiantnnij Linn. 

 1. A. polymorphum, sp. nov. 



Plant small, gregarious, caespitose in small tufts, each one 

 usually consisting of 3 living fronds that are sub-erect but often 

 defiexed from base of frond. Root-stock small, about % inch, 

 composed of several broken purple-brown stipites ; roots fibrous, 

 hairy. Fronds very membranaceous almost translucent, glab- 

 rous, grass-green, sub-linear-ovate, attenuate, simple pinnate 

 (in their normal state), 2-3 inches long, broadest at base and 

 there f-1 inch wide; pinnae 8-12-jugate, alternate, free, close 

 and distant, somewhat semi-orbicular, the anterior margin much 

 arcuate, the lower margin arched nearly to correspond, apex 

 rounded, base sub-truncate or excised in a curve and so imbri- 

 cating rhachis at the upper angle ; the superior and apical 

 margins of pinnae largely crenate-lobed ; lobes rounded, every 

 alternate sinus deeper and bearing a sorus distant from outer 

 margin of pinna, every pinna usually soriferous, and decreasing 

 gradually in size to apex, all petiolate, the dark petiole extending 

 a short distance into the pinna at lower basal margin, the upper 

 pinnae are sometimes quadrilateral ; the lowest pair of pinnae 

 much the largest, each pinna £ inch long by J inch broad ; the 

 terminal lobe small, rhomboid, obtuse, sometimes bearing an 

 involucre at the extreme tip. Veins branched, dichotomous, 

 free, rather distant, flabellate in smaller pinnae and at base of 

 larger pinna, the principal vein parallel with and close to the 

 lower margin, branches unilateral ; apices of barren veins curv- 

 ing over involucre on both sides between it and the margin of 

 pinna. Involucres large, distant, orbicular or sub-reniform- 

 cordate, flat, closely appressed, white with broad wrinkled 



* " Trans. N.Z. Inst.," vol. xii., p. 363. 

 t " Trans. N.Z. Inst.," vol. xv. p. 306. 



