2 I 6 
The Meeting of the British Association. 
Professor Bottomley’s success in greatly increasing tomato 
crops by the inoculation of nitrogen-fixing bacteria previously 
cultivated in tomato juice, and in inducing the bacteria to live in 
the cortex of the roots of wheat-plants is of obviously great 
importance both scientifically and economically. 
Morphological Papers. 
The main result of Professor Bovver’s account of his com¬ 
parative work on the Embryos of Pteridophytes was the conclusion 
that the principal organs of the plant are not laid down, as Goebel 
supposes, entirely on a basis of “ physiological opportunism,” but 
that the main axis of polarity is determined by the formation of 
the first segmentation, the centre of the epibasal segment corres¬ 
ponding with the stem apex. On the other hand, the relation of 
the polarity of the embryo to the axis of archegonium is quite 
variable, and so is the number and position of the first leaves and 
roots. Professor Bower was very successful in bringing into line 
with his general view a number of apparently anomalous cases. 
The sensation of the meeting from the anatomists’ point of 
view was the demonstration by Mr. Gwynne-Vaughan that the 
“ tracheids ” of Osmundaceae and many other Ferns are in reality 
not tracheids at all, but a peculiar type of vessel in which the pits 
are open perforations, and are also in free communication, one 
with another, in the thickness of the wall, by the disappearance of 
the middle lamella, so that the walls of the xylem elements are really 
skeletons built up of corner columns joined by horizontally running 
pairs of bars. It is not, perhaps, altogether creditable to fern- 
anatomists that they have so long missed this elementary fact of 
structure, which can be very readily demonstrated. 
Professor Oliver read an interesting description and discussion 
of Williamson’s palaeozoic seed Physostonm elegatis , nearly related 
to Lagenostoma. He regarded it as being one of the most primitiv e 
types of Pteridosperms yet discovered. 
Mr. D. M. S. Watson described the cone of Bothrodendron 
( Lepidodendrou) mundum as practically a Lepidostrobus with the 
radial extension of the sporophylls very much reduced, a state of 
things we should expect from a consideration of the vegetative 
organs. 
