258 MR. A. S. HOENE— A CONTEIBUTION TO 



ill Text-fig. 4. The position of the bracteole is marked hr. Only five bundles, indicated 

 by the letters a-e, extend throughout the ovary-wall. The bundles a, h are on the side 

 opposite the bracteole, and the remainder on the side adjacent to it (A-D) . The bundle a 

 is connected with the stamen stl\ h with the petal pe 1 and stamen sfi-, o with pe 2, st 3, 

 and pe^i d with st 4 ; and ^ with pe 4, st 5, and pe 5 (E, E, G). It is evident, therefore, 

 that all the petals and stamens, with the exception of st 1, pe 1, and st 2, are connected 

 with the bundles extending in one side of the ovary- waU— the side bearing the placentae ; 

 so that a special enlargement of one part of the original wall— that opposite the placentae- 

 seems to have taken place. Besides the principal bundles, two smaller ones, x and ^ (B), 

 are present, situated between b and c and e and a respectively. These die out upwards 

 after branching and anastomosing with the adjacent principal bundles. Branches are 

 shown at x and y (C). Figure G represents a transverse section of the model at the 

 level a-j3 shown in PI. 30. It will be observed that small branches extend inward 



from the principal bundles just belojv the point of insertion of the stamens and petals — 

 for instance, the branch d from pel and d2 from st2. These branches represent the 

 orin-inally free dorsal and lateral carpellary bundles of the primitive flower. Similar 

 branches occur in Sambucus, but they are entirely absent in Leycesteria, as mentioned 

 above. Within the single series made up of principal and auxiliary bundles {x, y) there 

 is another bundle, ax (A-D), which extends towards the placentae and divides just below 

 the ovule to form several small strands (D). Some of these collect to form the single 

 ovular bundle. The remainder collect to form three strands, ov 1, ov 2, and ov 3, which 

 extend upwards into the three placentae,^/ 1, pi 2, and/^Z 3 respectively (E). Thence they 

 extend into the style, where they alternate with the above-mentioned dorsal branches. 



Hence it is clear that the bundle 



a 



the extension of its branches into the 



placentae, does not follow the course normally pursued by a peripheral bundle that 

 relates specially to a parietally-borne ovule, but it is, on the contrary, analogous to the 

 entire axial system of the Caprifoliaceae with multilocular ovaries (Text-fig. 2). It is, 

 therefore, not unreasonable to suppose that the bundle has been actually displaced from 

 an axial to a peripheral position during the progressive abortion of the now rudimentary 

 compartments. Assuming this to be the case, and taking also into consideration the 

 morphological details already described relating to the ovule itself, together with the 

 facts that rudimentary ovules are sometimes situated immediately above the fertile ovule 

 and that rudimentary ovules do not arise from the placentae [pi 2, pi 3) on the side of 

 the fertile loculus, there is not the least doubt that the ovule now parietally situated was 

 originally axially borne, but has sufi'ered displacement concurrently with the displacement 



of the septa and axially extend 



This solution of the morphology 



of the ovary brings Viburnum into line with the remaining Caprifoliaceae 



Summary. 



L 



1. The Caprifoliaceae show a complete series in the direction of abortion in that part 

 of the ovary corresponding to the parietal portion in Leycesteria. The parietal region 

 is rudimentary in the pluriovulate carpels of Sy mphoricarpus and in Viburnum. - It is 



