A di ae 
COLLECTED BY MR. SPRUCE. 9 
transparent white, assumed by the whole of these plants, stem, scale- 
like leaves, and flowers, it is certain that the roots derive their nourish- 
ment from dead and rotten, not from living vegetables. Nor are these 
peculiarities of colour characteristic of any particular type of organiza- 
tion, for the species known belong in nearly equal numbers to three 
very different groups of plants, Gentianee amongst dicotyledons, and 
Burmanniacee and Triuridee among monocotyledons, two at least of 
these families having genera, if not species, closely allied to them, with 
ordinary green leaves and stems. The physiological cause of their ab- 
normal condition remains therefore still to be investigated. 
Mr. Spruce's expedition has added much to our catalogue of these 
species. He found them particularly to abound in the forests of the 
Rio Uaupés, and other tributaries of the Rio Negro. They are there 
generally known to the Indians by the name of Jurupari-erenuana, that 
is, “ Devil's beard ;” “but assuredly,” adds Mr. Spruce, “the Devil is 
not so black as he is painted, if these pretty things resemble anything 
about his sable majesty." The specimens he has sent home are care- 
fully collected and dried, and have afforded ample materials for com- 
pleting the definition of the genera and species to which they belong; 
although, in some cases, the extreme tenuity of the flowers, and conse- 
quent difficulty of ascertaining the precise forms of their more delicate 
parts, leave a few points yet uncertain, which can scarcely be satisfac- 
torily cleared up without the examination of the living plant. 
Such of these species as belong to Gentianea, chiefly Voyrias, have 
already been described in the last volume of this Journal. I propose 
now to enumerate those which are comprised in the two above-men- 
tioned monocotyledonous families. 
The TRIURIDEA were first proposed as a distinct Natural Order by 
Mr. Miers, in the 19th volume of the Transactions of the Linnean 
Society of London. He afterwards, in a monographieal paper in the E. 
21st volume of the same work, entered into more details on their  — 
structure and affinities, giving at the same time descriptions of all the — 
species known to him, illustrated by drawings executed with his usual 
neatness and accuracy. Two Javanese species have been since figured- 
and described by Blume in his Museum Botanicum Lugduno-Batavum, 
and the Order will now probably maintain its ground as a substantive — — : 
group, allied to Alismacee in its free apocarpous gyncecium and exal- — — 
buminous embryo, but differing chiefly in its valvate perianth, always — = 
VOL. VII. 
