an archaic type of Seed from the Palaeozoic Rocks. 95 
this way, it is difficult to understand the significance of the ‘ protruding 
endospore 5 as figured for L. ovoides (Miss Benson, loc. cit., Fig. 2, p 2 e), unless, 
as seems possible, the full history of these tubes has not yet been recovered. 
In the case of Physostoma it is, of course, just possible that the cell reticulum 
d (Fig. 30) may have been carried clear of the grain by the escaping sperms, 
though there is nothing in the preparation to indicate that d has any 
relation, except juxtaposition, to the pollen-grain a. These, however, are 
matters on which a decision is impossible till further data are forthcoming. 
The point of immediate interest is the detection in two related seeds of 
bodies whose presence in and about the pollen-grains is difficult to account 
for except as spermatozoids. The two sets of bodies show a close agreement 
in occurrence, form, and preservation, whilst the large dimensions of the 
supposed sperms of L. ovoides (40x30 //, as compared with 20x15// in 
Physostoma) accords with a similar relation in the size of the pollen-grains 
in the two cases. 
Apart from some quite abnormal product of disintegrating protoplasm, 
which cannot be profitably discussed, these bodies must be regarded either 
as organisms parasitic on the pollen-grains, or as petrified spermatozoids, the 
normal product of pollen-grain development. These and other contem- 
porary seeds are commonly attacked by fungi, and often show the mycelia 
and vesicles or spores with admirable preservation. 1 But careful comparison 
with numerous fungal vesicles that have come under my own observation 
has failed to convince me that these bodies are to be explained away as 
fungal productions. Some day, let us hope, expert mycologists may turn 
their attention to the fungal remains that abound in the petrified tissues of 
Palaeozoic plants. Till such critical studies are forthcoming a final decision 
on the nature of these supposed sperms is perhaps not possible. Subject to 
this reserve, I have no hesitation in expressing the opinion that the case 
for regarding these naked, sub-reniform bodies as spermatozoids is a strong 
one. As Miss Benson justly remarks, the discovery of spermatozoids in 
Ginkgo and the Cycads has paved the way for their detection in the seeds 
of Pteridosperms. 2 Now that attention has been drawn to the matter from 
several quarters, it may be hoped that additional and even more convincing 
specimens may come to light. 
7. The Vascular System. 
In its fundamental features the vascular system shows agreement with 
that of Lagenostoma Lomaxii. It may be recalled that in this seed the 
vascular supply is derived from the chalazal bundle, which enters at the 
seed-base, by its subdivision into a whorl of nine bundles which range them- 
selves symmetrically around the nucellus, and pass distally into the loculi 
1 Cf. Oliver, Notes on Fossil Fungi, New Phyt., vol. ii, p. 49. 
2 Miss M. Benson, loc. cit., p. 412. 
