242 FLORAL STRUCTURE AND ANATOMY IN THE FAMILY GOODENIACEAE DUMORT. By R. C. Carolin, University of Sydney. (Forty-five Text-figures.) [Read 29th July, 1959.] Synopsis. The floral anatomy of most genera in this family has been examined. It is concluded that the ovary of the Goodeniaceae is 4-carpellary, although various reductions and fusions obscure this. The ovary is fairly constant in form ; a basal 2-locular zone, a medial unilocular zont and an uppermost 2-locular zone, the latter two being-sterile. The relative sizes of these zones give the appearance of partial or complete 1-locular or 2-locular conditions. Solidifica-tion of one loculus may also give an apparently 1-locular condition. The inferior condition of the ovary may, in general, be considered to have arisen by fairly superficial mass growth, i.e., by fusion of the outer floral parts to the ovary. The evolution within the family is considered in the light of these investigations. It is noted that floral form alone hardly indicates a Campanulaceous origin. , Intboduction. The use of vascular patterns as a guide to structure has been a controversial technique. The crux of the problem appears to be the lack of knowledge of tlic fundamental cause of the initiation of a vascular strand. Puri (1951), Douglas (1944, 1957), and Eames and Macdaniels (1947) have summarized the arguments in favour of the conservative nature of vascular patterns. It is not intended to reiterate these arguments, suffice it to say that they appear reasonable. These patterns are controlled by the genotype of the plant and, because of their relative constancy, it can be assumed that the genetic systems responsible for them are well "buffered" against interference from the environment. The numerous cases of vascular strands pointing to the assumed positions of aborted organs implies that this genetic system is "conservative", i.e., new floral forms are superimposed on the previous vascular structures. Thus the vascular pattern of the flower can be used as a guide to changes in genotype, i.e., phylogeny. Colozza (1907, 1908) has described the vegetative anatomy and Brough (1927) examined the ontogeny of the flower of a single species. Saunders (1939) gives some data on a few genera; this is not complete and the interpretation is coloured by the theory of carpel polymorphism. This theory is considered to be an unnecessary com-plication. Material and Methods. Mature flowers and often young fruits were embedded in wax in the usual manner using chloroform as the wax solvent. Both transverse and longitudinal sections were cut at a thickness of 15/*. The sections were stained with crystal violet and counter-stained with erythrosin. In most cases fresh material was fixed in formalin-acetic-alcohol. In a few cases herbarium specimens were soaked in warm detergent before embedding in wax. The results are presented as diagrams in the main; only a few of the drawings of the serial sections have been reproduced here. In view of the fact that a number of species are known to show variability in their floral vascular patterns (Hall, 1956) a number of specimens (between 5 and 15) were examined for each species. The nomenclature of the vascular strands is that used by Eames and Macdaniels (1947). Observations. The carpels appear to be considerably modified and the loculi walls are probably formed by several carpels. The term pseudocarpel is therefore used in this presentation of the results to include the walls of each loculus and the corresponding part of the septum (see below). Proceedings of the Linnean Society of New South Wales, 1959, Vol. lxxxiv, Part 2.
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