APOGAMY 53 
found, either showing normal structure or various modifications of it. But 
in other cases, which have been described in detail by Lang,! the 
apogamous developments may diverge far from the normal in point of 
the number and position of the parts. Originating by direct vegetative 
growth from the tissues of the thallus, in place of the normal sequence 
and position of the parts the several constituents of the sporophyte, root, 
leaf, sporangium, may appéar without order or numerical rule: ten or 
more roots have been found apoga- ’ 
mously produced upon a prothallus 
without other parts of the sporophyte 
(Fig. 34): sporangia have been ob- 
served without sporophylls, originating 
directly from a formless mass of 
sporophytic tissue apogamously pro- 
duced on the prothallus (Fig. 35), 
or even, in an extreme case, from 
the prothalloid cells of the archegonial 
wall (Fig. 36). The irregularity of 
such growths must be taken into 
consideration in their theoretical 
interpretation, as will be seen later. 
Among the Archegoniatae apogamy 
has hitherto been observed in a score 
or more of species of Ferns, belonging 
to the Osmundaceae, the Hymeno- 
phyllaceae, and chiefly to the Poly- 
\podiaceae; and examples are also 
recorded from the Marsiliaceae. In 
the Bryophytes, the Lycopodiales, 
and the Equisetales no cases are as oe 
yet recorded. It may be noted, how- Nephrodium dilatatum, Desv., var. cristatum 
ever, that similar phenomena have ra, Frotallod cylindrical proces beating 
been observed in, Flowering Plants, poner Sem oe the osc: side: anion the up are 
such as Adchemilla, Thalictrum, * uniles associated with ramenta. 
Antennaria, and‘ Taraxacum.? 
Turning now to Apospory,® that is, the transition by direct vegetative 
growth from the sporophyte to the gametophyte without the intervention 
of spores, instances are recorded from the Liverworts (Amthoceros, Lang),* 
from the Mosses (Hypnum and Bryum, Pringsheim,’ Ceratodon, Stahl,® 
1 Phil. Trans., vol. cxc. (1898), p- 187, etc. 
2¥For references see Strasburger, Flora, 1907, p. 139. 
3 The term ‘‘Apospory” was introduced by Vines, in an article on the ‘‘ Proembryo 
of Chara,” Journal of Botany, 1878, p. 355-. 
4 Annals of Botany, vol. xv., 1901, p. 503. 5 Pringsh. Jahrb., xi., 1877. 
8 Bot. Zett., 1876, p. 689. 
