growth, but less repeatedly compounded, having its secondary branches 

 nearly bare of ramuli, and drawn out into long, circinate points, sometimes 

 passing into tendrils, and then clasping round any neighbouring object. 

 The cystocarps have not yet been observed. Stichidia are common, and 

 are found irregularly scattered over the branches and ramuli, springing 

 either from disc or margin ; they are subsessile, lanceolate, acute, and con- 

 tain a single or double row of large tetraspores. The substance of the frond 

 is softly cartilaginous, juicy and tender, at first somewhat crisp, but soon 

 growing flaccid in the air, and in drying the plant closely adheres to paper. 

 The colour, when growing, is a grey, or light greyish-fawn, reflecting pris- 

 matic tints ; but it very soon assumes a bright rose-red in the air, or instan- 

 taneously if plunged into fresh-water, and this rosy colour is retained in the 

 dried plant. 



The genus Sarcomenia, Sond., was founded on a plant from 

 Western Australia, at first sight very unlike the subject of the 

 present Plate, but bearing a strong resemblance in habit to Be- 

 lesseria hypoglossum. Having had opportunities of seeing both 

 plants in a living state, I am more confident in referring them 

 to the same genus. The substance of the frond is similar, and 

 both are remarkable for a singularly rapid change of colour from 

 an iridescent-grey or fawn to a rose-red, when removed from the 

 sea or when thrown into fresh- water. So far as known, the 

 fructification also agrees. The difference is thus reduced to one 

 of habit, S. hi/jmeoides being nearly cylindrical, while S. deles- 

 serioides, Sond., is foliaceous. But (as I hope to show in a 

 future number) the frond in S. delesserioides varies greatly in 

 breadth, and in some varieties is so very narrow as to become 

 nearly filiform, and such specimens may be even confounded 

 with our present plant. My first doubt, therefore, with the liv- 

 ing plants before me was, not whether they were of different 

 natural genera, but whether they were not extreme forms of one 

 variable species ! 



Pig. 1. Sarcomexia hypneoides, — the natural size. 2. A small branch, with 

 ramuli and stichidia. 3. Longitudinal semi-section of the frond. 4. A 

 transverse section. 5. A pair of stichidia: — the latter figures variously 

 magnified. 



