Mr. GnirrITH on the Ambrosinia ciliata of Roxburgh. 275 
TAS. AL 
Fig. 7. Ovule at a very early period, and before hairs are developed from the surface of the 
placenta: a. marks the site of the constriction ; b. papilliform nucleus. 
Fig. 8. Ditto, more advanced. The nucleus projects considerably beyond the margins of 
the cup formed by the enlargement of the annulus. The cellular hairs are now 
developed; some even exceeding the ovulum in length. A fascicle of vascular 
tissue is seen passing to the base of the ovulum. 
Fig. 9. Longitudinal section of the integument of a more advanced ovulum, leaving the 
nucleus exposed. 
Fig. 10. Ovule more advanced; the tegument is cut away as well as part of the short funicle 
longitudinally. The nucleus is exposed, and seen to be entirely inclosed within 
the tegument. It has undergone no alteration in form. Along its centre and 
throughout its upper half, there is an evident excavation formed. 
Fig. 11. Longitudinal section of an ovule still more advanced. The irregular form of the 
cavity of the testa and the dilated inferior portion of that of the nucleus are 
distinctly visible. The embryo is still inclosed within the upper half of the 
cavity. 
Fig. 12. Embryo, from about the same period ; it is now clavate, its conical apex has become 
rather oblique, and on one side a depressed areola surrounded with a rather thick- 
ened margin is visible. 
Fig. 13. Longitudinal section of the nucleus of a more advanced ovulum, a portion of the 
base of the testa remaining. The apex of the nucleus is now perforated, and the 
lower portion of the cavity is still more enlarged, and is seen to be occupied by 
cellular membrane. The conical apex of the embryo is seen projecting beyond 
the apex of the nucleus. | 
Fig. 14. Nucleus, with portion of the base of the testa, still further advanced. 'The now 
enlarged apex of the embryo is seen projecting beyond the nucleus, and the ori- 
ginal conical apex has become more oblique. From the areola two teeth are seen 
to project; these are the rudiments of the outer processes of the plumula. The 
apex of the inclosed portion has now reached to the dilated part of the cavity. 
Fig. 15. rye from the same placenta but from another ovule. The radicle is more 
oblique, and the rudimentary processes, of which there are six, are more enlarged ; 
. none are developed from the centre of the areola. 
Fig. 16. A much more advanced ovule. The greater part of the testa is cut away; the 
nucleus and enlarged apex of the embryo are exposed ; the radicle still preserves 
its obliquely ascending direction, and there is still some degree of obliquity in the 
plumula. 
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