Armsteong. — Description of new Plants. 369 



On a new Species of Pleurosigma. 



[Read before the Philosophical Institute of Canterbury, 13th October, 1881.] 



Pleurosigma crookii, sp. nov. 



Frustule : front view linear, narrowing towards the truncated extremi- 

 ties ; length about eight times its breadth. Valve : side view, linear for the 

 greater part of its length and slightly sigmoidal towards the rounded ex- 

 tremities, making the flexum only terminal ; length, '0025 to '0040 inch. 

 Colour light brown. Striae obscure. Median line central, approaching 

 concave side near extremity. 



Hah. — Fresh- water, New Brighton. 



The genus Pleurosigma has not been found hitherto in New Zealand. I 

 believe 1 saw it a few months ago in a very small gathering which I obtained 

 from Ngapari, Fernside, but as the frustules were so few in number I 

 could not examine them satisfactorily. The present species occurs in con- 

 siderable numbers in the ditches which drain New Brighton swamp. 

 Whenever the median line is not absolutely central, it approaches (in the 

 species figured by Smith) the extremities, more or less nearly on the convex 

 side. In the present species the line draws slightly nearer to the concave 

 side ; and the frustule is smaller than any described in Mr. Smith's work. 

 I have therefore ventured to consider it a new species. 



It would probably be a good test object. 



Plate XXII,, fig. 3 : a, front view ; h, suture ; c, side view. 



Aet. L. — Description of new Plants. By J. B. Armsteong. 

 [Read before the Philosophical Institute of Canterbury, Brd March, 1881.] 

 Asperula fragrantissima, n. sp. 

 The Strong-scented Woodroof. 

 Diff. char. — Perennial, matted. Flowers in clusters, pedunculate. 

 Description. — A small creeping perennial bright-green herb (black when 

 dry) forming dense broad patches 1-3 feet across, scarcely raised above the 

 surface of the ground. Steins wiry slender reddish 6-15 inches long, 

 branching freely and sending down wiry roots. Branches slender, round, 

 glabrous or glandular pubescent. Leaves sessile, entire, in whorls of 4 (2 

 opposite leaves and 2 leaf-like stipules) iV"^ i^ch long or more, linear- 

 oblong, obtuse, rarely sub-acute, not awned, glandular, dotted and slightly 

 pubescent on both surfaces, rather succulent in texture, flaccid when dry. 

 Floivers very numerous, creamy white tinged with rose-in-bud, very fragrant, 

 in axillary clusters of 3-8, rarely only 1, on branched peduncles, which are 

 ^-^ inch long or more, glandular-pubescent and rather stout for the size 

 of the plant. Calyx reduced to an extremely short tube and adnate with 



