442 
PROCEEDINGS OF THE BRITISH ASSOCIATION. 
Mr. J. Smith exhibited to the meeting two species of undescribed shells of the 
genera Fusus and Serpula. 
A paper was announced, but not read, by the Rev. J. Reade, “ On the solid 
Materials found in the Ashes of Plants and animals.” 
Professor Lindley made some remarks ‘‘ On the structure and affinities of 
Orobanckacecs!’ He stated that this order had been usually placed near Scro- 
phulariacecB^ and in his Natural System he had included it in the Scrophulal 
alliance. In their didynamous stamens, superior ovary, and monopetalous 
flowers, they resembled Scrophulariacece. Schultz had placed this order near 
Gentianacece^ on account of their fruit and placentation resembling those of this^ 
order. Other botanists had placed Orohanchacece near NLonotropaceae^ on account 
of their membranaceous foliage and parasitical habits. One important point in 
which they differed from Scrophulariacece^ was the position of their carpels, with 
respect to the axis of inflorescence. In Orohanchacece the carpels were right and 
left, or perpendicular to the axis, while in Scrophulariacece they were fore and 
aft, or parallel to the axis. This pointed out another affinity with Gentianacece^ 
which had its carpels in the same position. With regard to its affinity to 
Monotropa^ there was a point which had been much overlooked by botanists, the 
presence and absence, or large and small quantity, of albumen in the seeds of 
plants; he had found this a very constant character, and one of the best for 
indicating the affinities of plants. Both Monotropacece and Orohanchacece were 
distinguished for a minute embryo, lying in a large quantity of albumen. Mono¬ 
tropacece was a polypetalous order, but its structure generally compelled botanists 
to place it amongst monopetalous plants, near Fyrolacece and Ericacece. He 
remarked, by the way, that the division of plants according to the presence or 
absence, cohesion or non-cohesion, of the petals, was very artificial, and hoped 
that it would soon be abandoned. He thought that the affinities of Orohanchacece 
were stronger with Monotropacece^ Pyrolacece^ and Gentianacese^ than with any 
other orders. The Professor then made some remarks “ On the Placentation 
of Orobanche" which he said had made him doubt the correctness of the present 
theory of the situation of the placenta. It was generally supposed that the 
seat of the placenta in the carpellary leaf was its margin, so that it would be 
necessarily placed alternating with the dorsal suture or pistil. Exceptions, how¬ 
ever, frequently occur, as in Parnassia^ Papaveracece^ &c .; and the placenta is 
spread over the whole surface of the carpellary leaf, or on various parts of it. 
In the carpels of Orohanche there are evidently two placentse, but having no 
communication with the margin of the carpellary leaf. He therefore inferred 
that any part of the surface of the carpellary leaf might become ovulized. He 
was borne out in his opinion by the fact that leaves which occasionally produce 
buds, produce them from all parts of their surface, as seen in Ornithogalumy 
