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604. DR. M. T. MASTERS ON THE PASSIFLORACEZ. 
three of the five sepals were already marked out (fig. 8). Ina bud still m eu 
all five sepals were observed surrounding a pentagonal disk (fig. 9); and it was further 
noticeable that the sheath or lower portion of the sepal was the part first protruded, and 
that the little corniculus on its dorsal surface near the apex was not formed till subse- 
quently. The corniculus appears to be the analogue of the petiole. Payer states that 
two sepals are anterior or superposed to the primary bract (i. e. sepals 1 and 3, numbered 
in the order of their development), two lateral (4 and 5), while sepal no 2 is posterior; but 
I have reason for doubting if this is the exact order in all cases, as will be subsequently 
explained. : 
In a flower-bud still more fully developed the sepals were larger, but retained their 
inequality of size. At the angles of the central pentagon were now to be seen five small 
tubercles, all of the same size and simultaneously developed ; these correspond to the five 
petals (fig. 10). These tubercles gradually exchange their globular form for an oblong 
flattened shape. In a bud in a moreadvanced state of development the sepals and petals 
had increased in size; and five staminal tubercles opposite to the sepals were visible, the 
central disk remaining as before, flat and pentagonal (fig. 11). Next in succession appear 
three small tubercles on the central disk; these represent the three styles or the upper 
portion of the carpels. "They are at first perfectly separate one from the other, and leave 
between them in the centre a slight depression (fig. 12). As growth goes on, the three 
tubercles lengthen from below upwards; originally separate at the apex, disunion ceases 
after a little while, so that the carpels are congenitally inseparate below ; while the upper 
edges, at first free, become confluent one with the other, so as ultimately to form a closed 
ovary, the styles remaining separate (fig. 13). Previously to the complete closure of the 
ovary, however, the ovules begin to make their appearance, as will be explained further 
on (fig. 16). 
At this stage the anthers are fully sketched out, and even the filaments have made their 
appearance (fig. 14). Shortly after this the formation of the flower-tube, from the dila- 
tation and gradual excavation of the thalamus below the sepals, becomes perceptible, and 
about the same time the corona also makes its appearance in the shape of a series of 
small tubercles protruding from the flower-tube immediately beneath the petals (fig. 15). 
The order of development of the succeeding rows of the corona seems, so far as I have 
ascertained, to be different in different species; thus, after the formation of the upper- 
most row of the corona in P. quadrangularis the median series or operculum is developed, 
and the intermediate rows subsequently.. The urceolus or basilar corona at the base of 
the stamens is developed before the column or gynandrophore begins to lengthen. This 
latter organ, the stalk of the stamens and of the pistil, is the last of the floral organs to 
appear (fig. 18). : | 
Ovules.—The ovules present themselves in the first instance as small conical papillæ 
projecting from the placenta (fig. 19); these speedily become invested, from below up- 
wards, by a cellular tube, the seeundine. As this tube grows, the primary nucleus becomes 
Curved. After a little time a second envelope, the primine, is formed, so that the fully 
formed ovule is anatropal and invested by two coatings (figs. 20, 21). The arillus which 
surrounds the ripe seeds is not fully developed till after the fertilization of the ovule; but 
