276 MISS MARIETTA PALLIS ON THE 
part of sea- or river-borne sediments, and Letei and Caraorman, for instanee, 
have possibly been old land-surfaces *. 
The grindu Sáráturile, north of St. George, is an interesting example of 
a composite grind. It is at present being covered by blown-sand, but its 
former origin is revealed by the few living remnants of the past salt- 
marsh vegetation, Statice (melini, Willd., and Juncus maritimus, Sm., for 
example, which project through the blown-sand. Here and there lagoon- 
deposited soils are present; that is to say, thin layers of very fine bluish silt, 
and to them the hardness and comparative goodness of the track across this 
sandy grind is probably due. , The foundation of this grind is certainly in 
places marine. 
APPENDIX B. 
The Willow Forest of the Danube in Rumania. 
A fringing willow forest consisting chiefly of Salix alba, Linn., is charac- 
teristic of the banks of the Danube practically up to Tulcea ; beyond, it 
ceases, except for a few large scattered trees along the St. George Chatal 
and for a few woods along the Stari Stambul fork of the Chilia Chatal. 
These fringing woods are narrow and more or less band-shaped and, in 
general, the trees are grouped together according to size, that is to say, the 
trees of the different groups are more or less of an age. Thus the later and 
earlier formed portions of the islands of the Danube can often readily be 
distinguished by the different sizes of the trees. 
These characteristics apparently follow from the practice of turning out 
horses and cattle to pasture on the embankments when the Danube is low. 
The animals destroy almost all the seedlings on the bank, but those scattered 
in the river manage to escape, even though the cattle enter the water when 
the weather is hot (see Pl. 28. fig. 2). Thus it is that the willow forest 
remains a narrow band, and does not die out along the banks of the Danube, 
but arises again and again as a fresh narrow band in front of the old one 
which in time vanishes. Incidentally, of course, the young trees in the 
water hasten the formation of land. 
The cattle and horses, as a matter of fact, do not confine their attentions to 
tree seedlings, but apparently to а great extent determine the herbaceous 
vegetation of the embankments and islands of the Danube in Rumania. The 
most numerous plants are unpalatable ones, for example: Althea officinalis, 
Linn., Lythrum Salicaria, Linn., Bidens tripartita, Linn., Senecio tomen- 
tosus, Host, Xanthium spinosum, Linn., Myosotis palustris, Roth, Symphytum 
officinale, Linn., Convolvulus sepium, Linn., Mentha aquatica, Linn., Urtica 
dioica, Linn., Euphorbia salicifolia, Host, and coarse hairy grasses. The 
dewberry, Rubus cæsius, Linn., is also very abundant, but nearly all the 
tops of its shoots are bitten off, only the lower hard and prickly parts of the 
plant remaining. I regret that the time at my disposal prevented me from 
preparing a complete list of this characteristic and interesting vegetation. 
* See Antipa, pages 103-104, op. cit. 
