294 Bower. — Some Normal and Abnormal 
the Bryophyta. I should, however, be disposed to leave 
open, for the present, the question, whether or not the flattened 
expansions of species of Trichcmanes and Hymenophyllum 
correspond to the flattened growths on the protonema of 
Tetr aphis and other Mosses, as well as the still larger question 
of the relation of the Moss-plant to the archegoniophore of 
Trichomanes. There is, however, a strong presumption in 
favour of these comparisons. The main conclusion may be 
accepted, viz. that the protonema of the Moss corresponds 
with the protonema of Trichomanes \ and this leads towards the 
conclusion given by Goebel in the following words, ‘ We may 
accordingly regard as the starting-point for the Bryophyta 
and Pteridophyta, Alga-iike forms, consisting of branched 
filaments,’ while it is also probable that in these ancestral forms 
the sexual organs were directly inserted on the filaments. 
It is a well-known fact, illustrated now in more than one of 
the great series of Vascular Cryptogams, that the conformation 
of the oophyte may vary considerably in forms in which the 
sporophyte shows greater constancy. This has been pointed 
out by Treub in his studies on the Lycopodiaceae 1 , in which 
he states his belief that the differences of conformation of the 
prothallus in various species of Lycopodium are not merely 
recently acquired. As reasons for this view he states that the 
differences are too great for that explanation, and that the 
young asexual generations are also dissimilar ; he concludes 
that the different characters of the prothallus may in that 
genus serve as genealogical data. It must be admitted that the 
want of parallelism between asexual and sexual generations 
in the species of Trichomanes hitherto described is less marked 
than that in species of Lycopodium ; but there is some similarity 
between the two cases, which is the more worthy of remark 
since the genera occupy somewhat similar positions with 
regard to the great series of the Bryophyta. Each is a near 
approach to the starting-point of a great series : in the one 
case the Lycopodinae, in the other the Filicineae. It is a 
1 Ann, Jard. Bot. de Buitenzorg, vols. iv-v. 
