174 CLIMBING PARASITES. GREEN-LEAVED PARASITES. TOOTHWORT. 
tered, lying on the damp earth for four or five weeks waiting for something to 
turn up. Not infrequently something of the sort happens, for another plant may 
germinate close by or extend a growing shoot from the vicinity and touch the 
Cuscuta seedling. In this event, the latter at once seizes the anchor thus thrown 
out, and winds round it. But if no support of the kind is to be had, the seedling 
must ultimately perish. It is, to say the least, a very remarkable thing that a 
filament, capable of developing suckers when adherent to a living plant, is not able 
in damp earth to produce any absorbent organs whatsoever. 
If the thread-like Dodder plantlet succeeds in seizing a support of any kind, 
either during the existence of the swollen extremity, or later, after it has been 
absorbed, it makes a single, or from two to three, coils round the prop, raises its 
growing point from the substratum, and moves it round in a circle like the hand 
of a watch. By means of these manceuvres, which look exactly like a process 
of feeling or seeking, the filament is brought into contact with fresh haulms 
twigs, and petioles belonging to other plants. To these it adheres, making once 
more two or three tight coils round them. Throughout, it is obvious that the 
growing point of the young Dodder rejects dead props, as far as is practicable, 
and shows a striking preference for living parts of plants. 
At each place where the Dodder is pressed in a coil against the support, the 
filament becomes somewhat swollen, and wart-like suckers are developed, which are 
usually situated close together in rows of three, four, or five (see fig. 35’). 
A piece of stem thus furnished with suckers or haustoria resembles a small 
caterpillar creeping up the supporting stem. These haustoria, arranged close 
together in rows, and corresponding in origin entirely to rudimentary roots, are at 
first smooth, but acquire soon a finely-granulated aspect owing to the walls of the 
epidermal cells projecting outwards. With the help of the papille thus formed, 
and especially through the action of a juice secreted by them, the suckers fasten 
themselves to the host. If the plant has been obliged to clasp a dead object for 
support, the wart-like processes flatten themselves against it and assume the form 
of a kind of dise, which exhibits no further development, and only serves as an 
organ of attachment; but, if the substratum is a living plant, a bundle of cells 
forces its way out from the middle of the haustorium and grows into the sub- 
stratum direct. The phenomenon here manifested is altogether characteristic. 
Each sucker from the time of its production exhibits a kind of core composed of 
cells arranged in regular rows, which, together with a few spirally-thickened 
vessels, constitute a bundle standing at right angles to the axis of the Dodder's 
stem. This bundle now breaks through the coat formed by the rest of the cells 
of the sucker and penetrates into the living tissue of the plant attacked (see fig. 
35°). Great force is exerted in the penetrating process. The closely-joined cells 
of the epidermis, and not infrequently a cortex of considerable density are pierced, 
and the bundle of cells often penetrates right into the body of the wood. Having 
once reached the interior of the host, the cells, till then bound together in a 
bundle, diverge a little, insert themselves singly between the cells of the host. 
