380 Boodle. — On some points in the 
about two or three cells thick, bordering on the sieve-tubes, 
is differentiated and should be regarded as belonging to the 
phloem. In roots collected in December, this zone of cells 
differed from the parenchyma below it in having very little or 
no starch, and in the dense granular proteid contents of many 
of the cells. The rest of the parenchyma may be called 
conjunctive b 
The roots of several other species of Ophioglossum are also 
monarch. Prantl 1 2 gives monarch roots as a character common 
to the whole section E uophioglossum , which includes twenty- 
seven species in his monograph 3 . Poirault 4 , however, states 
that this does not hold good, and that O. ellipticum is an 
exception. The two remaining species, in Prantl’s classification, 
are O. pendulum and O. palmatum . The former he describes 
as having triarch and tetrarch roots, and the latter diarch. 
O. pendulum has sometimes diarch roots, and an interesting 
fact (for comparison with O. vulgatum , &c.) is that monarch 
structure may occur as a modification in these roots. This 
was seen in the basal region of a rootlet 5 . The diarch rootlet 
is shown in transverse section in Fig. 5, and its monarch base 
in Fig. 4, which represents the stele of this rootlet where it 
passes through the cortex of the parent root. A comparison 
of Figs. 4 and 5 makes it pretty clear that the xylem-group in 
Fig. 4 represents the right-hand one in Fig. 5, and that the 
1 In Fig. 9 the distinctions between sieve-tubes and parenchyma are not clearly 
represented. The rather large elements, one to two cells thick, touching the 
endodermis, and marked ph , are sieve-tubes. The next two or three layers, 
including some rather small cells, are phloem-parenchyma ; the rest of the tissue 
down to the xylem is conjunctive parenchyma (/). 
2 Prantl, Beitrage zur Systematik der Ophioglosseen, in Jahrb. d. k. bot. Gartens 
zu Berlin, Bd. iii, p. 297. 
3 Many of these rank as synonyms in Hooker and Baker’s .Synopsis Filicum, 
where only six species are given under the section Euophioglossum. 
4 Poirault, Sur Y Ophioglossum vulgatum , Journ. de Botanique, t. vi, p. 71* 
5 This was clearly a true rootlet, not a case of dichotomy of the root as 
described by Rostowzew and Poirault for 0 . vulgatum. It is curious that 
dichotomous and monopodial branching should occur in roots of the same genus. 
Possibly the dichotomy may be restricted to the monarch roots; cf. Van Tieghem 
(Symetrie, &c., p. 108). In speaking of the root of 0 . vulgatum he says: ‘Si 
eile vient a se diviser, nous savons a Pavance que ce sera par dichotomies 
