28 Oliver and Salisbury . — On the Structure and 
nucellus and integument were joined, and between these two ran the four 
vascular strands which corresponded in position to the larger ribs. 
The lobes of the canopy internally have almost entirely disappeared, 
and only four tapering loculi remain, no doubt filled with soft tissue 
into which the vascular strands passed. The general appearance of the 
seed may be gathered from Text-figs. 9 and 10, which give restorations in 
longitudinal and transverse section respectively. 
3. The Testa. 
Although Conostoma anglo-germanicum resembled C. oblongum in the 
general features of its testa, yet the angling of the body of the seed, in 
the latter species obscure, was in the former marked by prominent external 
ribs, to the number of eight, symmetrically placed around the seed, which 
interiorly in this region formed a much rounded octagon (PI. Ill, Fig. 22). 
In the middle region, for about half the total length, the sides were 
nearly parallel, tapering gently below to a thick stalk ; whilst above, the 
surface curved rapidly inwards till the diameter diminished to about a third 
its maximum, and thence tapered abruptly upwards so as to form a conical 
tube 0-65 mm. high around the micropyle (PI. Ill, Fig. 26, m.co ., and 
Text-fig. 9). The eight ribs traversed the whole body of the seed and 
formed prominent winged expansions to the stalk (PL III, Fig. 21, R 
and r, and Text-fig. 30, R 1 R 2 . . ., r 1 r 2 . . .). The ribs exhibit an interesting 
differentiation of the alternating members ; four were large, and projected 
in the middle region about 125/x from the surface, and may be termed the 
major ribs (PL III, Fig. 22, R.) ; the alternating members, which were only 
about half as prominent, we may term the minor ribs (Pl. III, Fig. 22, r 1 , &c.). 
The relative thinness of the testa between the ribs, which only attains 
a thickness of on mm., coupled with the very marked prominence of the 
ribs, suggests that this latter feature may be of the nature of a mechanical 
adaptation. The differentiation becomes most marked at the apex ; here 
the minor ribs, which remain of nearly uniform width, follow the outline of 
the seed, but die out suddenly where the curvature of the surface alters as 
it passes into the micropylar cone (Text-fig. 9, m. col) ; the four major ribs 
continue their former gentle curvature above the shoulders of the seed, so 
that around the micropylar cone they become extensive wing-like expan- 
sions. A section cut at this level has the form of a four-rayed star, with 
the centre occupied by the micropyle (Pl. III, Fig. 23). Beyond the 
orifice of the latter the free pointed ends of the ribs projected, and their 
internal margins bounded the cup-like hollow in which the micropyle 
stood (PL III, P'ig. 24, R Y .e. and R 3 . e). 
A median longitudinal section passing through two opposed major ribs 
appears concavely mucronate (PL III, Fig. 26), and somewhat resembles 
a similar section through the apex of Stephanospermum , where perhaps the 
