Male Gametes in Pines and Allied Conifers. 171 
these rivers. At Lamberhurst it occupys the lower facings of the 
sandstone bridge which spans the River Teise and just before 
reaching Battle it is found occupying the sandstone escarpments 
by the roadside. At Ecclesbourne and Fairlight Glens, Hastings, 
it is found fruiting regularly in April. The plants however growing 
on the banks of the rivers do not fruit periodically except in those 
situations where they are not liable to prolonged submersion during 
periods of flood, such as upon arches bridging streams. From the 
fact that Fegatella conica and Pellia epiphylla are found so extensively 
lining water courses and rarely elsewhere we may reasonably 
conclude that they owe their present distribution entirely to water 
carriage, not only of spores, but also of detached plants during 
periods of flood. We may also conclude that since these plants are 
able to complete their life cycle annually under the present conditions 
of our climate they have a greater chance of survival with us than 
Dumortiera and Lunularia, which show a waning sexual activity. 
ON THE MEANING OF THE VARIOUS FORMS OF THE 
MALE GAMETES IN THE PINES AND ALLIED 
CONIFERS. 
By E. M. Cutting, M.A., F.L.S., 
Demonstrator in Botany at Birkbeck College , London. 
T N 1892 Strasburger (17) described two unequal male cells as 
the product of division of the body cell in Pinus sylvestris. 
Each of these cells was surrounded by a very small amount of 
cytoplasm. As one would expect from the above description, and 
as Strasburger clearly shows in his figures 43 and 44, not only the 
cells but also the nuclei are of slightly different size. In 1894 
Dixon (7) in describing the male nuclei of Pinus sylvestris speaks of 
them as being of about the same size, evidently meaning to suggest 
by this that, as far as he could see, they were not quite equal, but 
very nearly so. In his figures showing this dissimilarity the nuclei 
are situated in the upper part of the pollen tube, that is to say the 
inequality is present at quite an early stage. 
