136 DR. J. D. HOOKER ON THE GROWTH AND COMPOSITION 



tissue, and causing that fragility of that part of the ovarium which led to Griffith's sup- 

 posing that the ovarian cells were formed subsequently to the freely developed ovules. The 

 true stigmatic canals I iind terminating in the papillose fimbriated teeth of the annulus. 



i. Towards the period of expansion of the flower (fig. 6), a considerable change is found 

 to have taken place in the relative proportions and positions of the ovary and perianth. 

 Owing to the upward direction of the development of the ovary, it is now half-superior, 

 in the usual acceptation of that term. The stamens (fig. 9) form a closely imbricating 

 whorl, appressed to the surface of the annulus, the stigma-like head of the central column 

 appearing in the space between their apices, and the five cellular fringed teeth of the 

 annulus also projecting. 



On removing the stamina, the protuberant surface of the annulus is more strongly 

 5-ridged, and the groove round its orifice is deeper. A double vertical section shows 

 that the column is much elongated, and its surface covered with a more evident cuticle, 

 as are its capitate stigma-like apex and the adjacent walls of the annulus. The external 

 surface of the annulus is also covered with a similar cuticle, except at the groove sur- 

 rounding its orifice, and on the fimbriated teeth, which are manifestly the true stigmata, 

 and are formed of loose papillose tissue (fig. 13). The ovarian cavities are at this period 

 found to be considerably displaced, some being carried a little upwards and others down- 

 wards, so that two or three are often exposed at one vertical cut. Unrollable spiral 

 vessels are now found in the vascular cord that passes dovmwards from the ovules, but 

 none in the transparent line that passes upwards from the ovules parallel to the inner 

 waUs of the annulus, these lines being formed of loose conducting tissue, terminating in 

 the stigmatic teeth at the orifice of the annulus. A transverse section of the annulus 

 (fig. 10) now shows five pale spots of loose cellular tissue ; these are the stigmatic canals, 

 placed very close to the inner walls of the annulus. 



5. At the period of expansion (fig. 7) the stamens are found to have risen from the 

 surface of the annulus, and the stigmatic teeth are sphacelated and covered with pollen- 

 grains, which adhere to its surface and to the surface of the mouth of the tube ; but I 

 have not succeeded in tracing the pollen-tubes into the stigmatic canals, probably owing 

 to the excessive minuteness of the pollen in this plant. 



The differences between my own and Mr. Griffith's observations are, first, in the ovules 

 being developed in cavities of the ovarium, and not free at the base of the conical central 

 body, which he has mistaken for a placental development ; secondly, in the presence of a 

 cuticle over the whole surface of the said body and on the contiguous walls of the 

 annulus ; thirdly, in the absence of any vascular bundles passing from the ovules upwards 

 into the annulus ; and fourthly, in the absence of any stigmatic puncta at the base of the 

 central column, and of stigmatic lines passing from these inwards to the ovules. The 

 groove round the mouth of the annulus, the absence of cuticle over it, and the structure 

 and consequently the stigmatic nature of the teeth of the annulus, seem further to«have 

 escaped Mr. Griffith's notice. 



If my observations are correct, the composition of this very remarkable ovarium is 

 reducible to the known modifications of carpellary structure, and may be regarded as 

 consisting of a whorl of five connate carpels adnate to a central fleshy axis or torus ; 



