6i 8 
Notes . 
circ. \ lin. longi. Coronae squamae, 5, angustae, tubo stamineo 
affixae, membranaceae, apice alte 2-fidea, lobis longiusculis recurvis. 
Anther ae erectae. Stigma complanatum, obsolete 2-lobatum, vix ex 
antheris exsertum. Folliculi tenues, teretes, leves, acuminati, i-|-2j 
poll, longi. Semina pilis longis albidis sericeis coronata. 
Borneo: Kuching, Shelford , near Kuching Lake, Haviland 2015. 
Mr. Shelford states that his specimen is epiphytic on a tree which 
he believes to be a species of Ficus. 
H. H. W. PEARSON. 
STUDIES IN THE MORPHOLOGY OF SPORE-PRODUCING 
MEMBERS. NO. V. GENERAL COMPARISONS, AND CON- 
CLUSION \ — This concluding Memoir contains a general discussion 
of the results acquired in the four previous parts of this series, and 
of their bearing on a theory of sterilization in the sporophyte. The 
attempt is made to build up the comparative morphology of the 
sporophyte from below, by the study of its simpler types ; the higher 
and more specialized types are left out of account, except for occasional 
comparison. It is assumed for the purposes of the discussion that 
alternation of generations in the Archegoniatae was of the antithetic 
type, and that apogamy and apospory are abnormalities, not of 
primary origin. 
After a brief allusion to facts of sterilization in the sporogoma 
of Bryophytes, the similar facts are summarized for the Pteridophytes. 
It has been found that examples of sterilization of potentially spore- 
genous cells are common also in vascular plants, while occasionally 
cells which are normally sterile may develop spores. Hence it is 
concluded that spore-production in the Archegoniate plants is not in 
all cases strictly limited to, or defined by, preordained formative cells, 
or cell-groups. A discussion of the archesporium follows, and 
though it is found that in all Pteridophyta the sporogenous tissue is 
ultimately referable to the segmentation of a superficial cell, or cells, 
still in them, and, indeed, in vascular plants at large, the segmenta- 
tions which lead up to the formation of spore-mother-cells are not 
comparable in all cases; in fact, that there is no general law of 
1 Abstract of a paper read before the Royal Society on February 12, 1903, 
reprinted from the Proceedings. 
