Affinities of the Palaeozoic Seeds of the Conostoma Group . 13 
4. The Vascular System. 
Corresponding in position to the six ribs of the testa were six 
bundles which occupied the internal angles. These passed up just outside 
the nucellus till they reached a level slightly above the base of the 
lagenostome, where they turned upwards and entered the sclerotesta, 
accompanied by a strand of soft-celled parenchymatous tissue (R. 117, 
PI. II, Fig. 16, loci) ; thence they again curved inwards, probably ending 
at the limit of the hard testa close to the micropyle; here the accom- 
panying parenchyma, which gradually narrows towards the apex, dies 
out (Text-fig. 3, between B and a). 
Around the micropyle the hard testa was slightly lobed, the lobes 
corresponding in number and position to the vascular strands within ; to 
this lobing is due the internal asymmetry of the apex seen in some of 
the sections where they pass through a ridge on one side of the micro- 
pyle and through a ‘furrow’ on the other (R. no, PL II, Fig. 14; 
R. 123, PI. II, Fig. 19, i.ri). 
The apex of the hard testa in Conostoma was therefore very like the 
canopy of Lagenostoma Lomaxii , where likewise the lobes corresponded 
in number and position to the vascular bundles which passed into them. 
They did not, however, agree in position with the external ridging of 
the apex, which, as has been pointed out before, 1 was associated with 
the radial septa. The chief point of difference in Conostoma lies in the 
reduction of the soft tissue which occupied the loculi of the canopy to 
mere strands accompanying the bundles. The vascular bundles them- 
selves consisted of four to five elements (each about 10 p across) with 
delicate scalariform thickenings which occasionally exhibited fusion between 
adjacent bars. 
5. The Soft Integument . 
Surmounting the apex of the hard testa was a cap of soft-celled tissue 
(R. 122, PI. I, Fig. 3, s.ti) which was thickest around the micropyle, where 
it formed six free lobes (Mr. Watson’s specimen 268, PI. II, Fig. 12, /.) corre- 
sponding to the obscure lobing of the hard tissue below, and thinned out 
in the basipetal direction, ending just above the shoulder of the seed 
(Text-fig. 3). The only evidence that the vascular supply extended into 
this region is a very doubtful vascular bundle in one of the preparations. 
This soft tissue may have been of a secretory nature, supplying in part 
the necessary fluid for the process of pollination, by furnishing a drop 
mechanism as in Taxus. The specialized epidermis around the micro- 
pyle, to be described later, somewhat resembles the protective epidermis 
1 Oliver: On Physostoma. Ann. of Bot., vol. xxiii, p. 105. 
