896 Mr Gordon, On a new species of Physostoma 



The length of the new seed is probably greater than indicated, 

 since both sections are oblique, and 4 mm. would probably not 

 be an excessive estimate of the true length. The breadth is also 

 considerable, and indeed the almost globular shape of the seed 

 is striking. The base is rather flat and the micropyle is not 

 prominent. 



The seed at the apex shows a number of tentacular processes 

 and the outer surface is studded with small peg-like hairs. The 

 occurrence of these characters warrants its inclusion in the genus 

 Physostoma as lately defined by Oliver. 



All the Pettycur seeds I have examined are poorly petrified, 

 and this new one is no exception. The description must there- 

 fore be meagre. 



The nucellus is capped by the pollen chamber but there is 

 no dome-like projection of the nucellar apex into the cavity of 

 the pollen chamber. Indeed, in that region the seed is quite like 

 Conostoma and not Physostoma. Outside the membrane of the 

 nucellus the tissues are all decayed; only the vascular bundles 

 remain. Near the chalaza however and in one of the apical 

 processes a slight amount of delicate parenchymatous tissue 

 can be observed, but it is too fragmentary to warrant detailed 

 description. 



The outer layers of the integument have all decayed into a 

 structureless dark zone about "2 mm. thick. There are no ribs 

 on the outside of the seed, but the whole periphery is covered 

 with small dark dots. These lie in a zone concentric with the 

 seed and about "l mm. outside. Near the micropyle these dots 

 are seen to occupy the ends of short finger-like cells which clothe 

 the seed externally. They are quite similar to the peg-cells of 

 Lagenostoma and may be equivalent to the hairs on Physostoma 

 elegans. In this new specimen the hairs are equal in length all 

 over the surface. In outline the hairs are short and have rounded 

 ends. 



The most interesting part of the seed, however, is the raicro- 

 pylar end. There we find a pollen chamber in the usual position 

 at the apex of the nucellus. The orifice of this chamber is not 

 visible owing to the obliquity of the section and it is uncertain 

 whether there was a funnel-shaped aperture as in Physostoma 



