GOLD DUST OF NOTHOCHL^ENA. 369 



subjects of investigation in a well-filled stove-fernery. 

 This Platy cerium, for instance, has its fronds covered 

 with a gray hoar, which, on being magnified, is resolved 

 into a vast multitude of isolated groups of short slender 

 white filaments, radiating from a centre in a star-like 

 manner, from six to ten threads to each star. The 

 gold and silver ferns, too, already mentioned, afford 

 pleasing objects. The very lovely little Nothochlcena 

 flavens I have just been examining ; and most charm- 

 ing it is. Under a power of 100 diameters, with 

 light reflected from a lieberkuhn, the under side of a 

 pinna exhibits an area which we might suppose sown 

 with flower of sulphur, which, however, has fallen in 

 tiny coherent masses, as if slightly damp, uniform in 

 size, and no thicker than a single layer. Over this 

 area the globular spore-cases are spread, in two bands, 

 parallel with the edges of the pinna, and running 

 from base to tip ; these bands, however, resolvable 

 into oblique lines of thecce, which follow the course of 

 the veins. They look like marbles, or rather bullets, 

 in which the seam of the mould may represent the 

 stout ring, which passes vertically over and round 

 each theca; the colour, a deep brown almost black, 

 with a rich warm hue appearing between the nodules 

 of the ring. The yellow dust, when carefully scraped 

 off with a needle-point, and spread on a slip of glass, 

 is found to be composed of loosely-adherent granules 

 of irregularly-ovate form, so minute that even with 

 very high powers, as 600 or 800 diameters, they 

 appear only as points ; and, when measured with a 



2A 



