70 Rhodora [March 



water that the sediment gathers about them and they offer firmer 

 hold for the higher plants. Sometimes, however, at least one species 

 of the higher plants is the first of living things to make an appearance 

 on the cliff. This may be a Saxifraga or a Chrysosplenium, and 

 these rock-loving, water-loving plants are often seen with only algae 

 to accompany them. Ferns and perennial herbs follow in due 

 course. 



A certain grotto in a mature state is well known to the writer. 

 It is located in the Blue Ridge near the town of Melrose, North 

 Carolina. Here in a deep mountain glen where the shade is heaviest, 

 a spring seeps over a concave rock and supplies to the shelving ledge 

 below, with its plant inhabitants, the continually fine drip of water 

 which semi-aquatic plants find so favorable to their growth. It 

 simulates, or rather it surpasses in effectiveness, the conditions in 

 flower gardens where a continuous spray of cool water is maintained 

 and where the soil is almost pure vegetable decay. 



Here every inch of the room is contended for by every sort of 

 plant — alga, moss, liverwort, fern, and flowering perennial. The 

 cascade itself is tamed by the extensive root-system above to a gentle 

 series of rivulets which run down the tangled masses of the algae. 

 The algae in this case seem more like lianes or other aerial plants 

 than those of ponds and pools. Such luxuriant Bryophytes as 

 Fegatella, Catherinea, and numerous species of Milium, have 

 matted the shelf rock all over and to a remarkable depth. Most 

 interesting of all is a marchantiaceous plant which, like the algae, 

 hangs suspended from the upper rock and serves to conduct the 

 rivulets of the seepage. It is a species of Dumortiera, and being 

 immersed in water, unlike so many others of its tribe, it has lost the 

 air chambers characteristic of the thallus of the Hepaticae. Only 

 rudiments of these organs remain, and the thin translucent emerald- 

 green of the long thallus makes it look more like a delicate seaweed 

 such as Ulva. Seen through the clear water of a mountain stream, 

 with the afternoon sunlight shining through it, or through the crystals 

 of ice in winter, it is one of the most beautiful of plants. 



The annual cycle cf this grotto is interesting. Observed in winter, 

 it is seen to be hung with icicles and still quite green with mosses 

 and liverworts. There are few algae to be seen. The big basal 

 rosettes of saxifragacious plants and the dead stalks of the summer's 

 perennials show themselves, and the grass-green leathery thallus of 



