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Telopea Vol. 6(4): 1996 
Surface waxes Epicuticular wax morphology may be significant for the higher-level 
systematics of some taxa. Barthlott & Frolich (1983) and Frolich & Barthlott (1988) 
identified several types of epicuticular wax, of which the Convnllaria-type (small 
wax platelets clearly oriented in more or less parallel lines) is largely restricted to 
some genera of Asparagales, Liliales and Burmanniales, and the Strelitzia-type (long, 
often curly, extruded wax ribbons) to some commelinoid taxa: certain Arecanae, 
Commelinanae, Zingiberanae and Bromelianae (although there are exceptions, e.g. 
the Strelitzia-type occurs in Dracaena). However, these types are by no means 
ubiquitous in the groups in which they occur, so their absence is not necessarily 
significant. Barthlott & Frolich (1983) and Frolich & Barthlott (1988) reported neither 
type in the five out of six genera of Dasypogonaceae that they examined, and our 
results have confirmed this: surface waxes are present but not oriented in parallel 
lines or long wax ribbons. These results are therefore inconclusive with regard to the 
systematics of this group. 
Stomata Anomocytic stomata (i.e. without subsidiary cells, using the terminology of 
Metcalfe 1961) are the most common mature stomatal type amongst Asparagales, 
although paracytic and tetracytic forms also occur, often in combination. Paracytic 
stomata have lateral pairs of subsidiary cells parallel to the long axis. Tetracytic stomata 
are surrounded by four subsidiary cells (two lateral and two polar). Both paracytic 
and tetracytic types are prevalent in the commelinoid clade, where anomocytic stomata 
are relatively rare. However, Tomlinson (1974) and others have suggested that an 
ontogenetic study is essential for systematic purposes, as similar mature types may be 
achieved by different ontogenetic pathways, and are therefore non-homologous. For 
example, in the paracytic stomata of Poaceae and many other commelinoid taxa 
(Cyperaceae, Juncaceae, Centrolepidaceae, Eriocaulaceae, Xyridaceae, Joinvilleaceae, 
some Commelinaceae, Marantaceae and Zingiberaceae), the subsidiary cells are derived 
by non-oblique divisions of the lateral contact cells adjacent to the meristemoid (guard 
cell mother cell). Similarly, in the tetracytic type of many commelinoid taxa (some 
Commelinaceae, Philydraceae, Cannaceae and Zingiberaceae), the subsidiary cells are 
derived from non-oblique divisions of the lateral and polar neighbouring cells. 
Conversely, the paracytic and tetracytic types of most non-commelinoid taxa 
(Agavaceae, some Amaryllidaceae, Asphodelaceae, Butomaceae, Cyclanthaceae, 
Orchidaceae, Philesiaceae, Pandanaceae) are often derived from oblique divisions of 
the neighbouring cells. However, this character is not entirely reliable as a taxonomic 
marker at the higher level. For example, some commelinoid taxa consistently have 
oblique cell divisions (e.g. Arecaceae, Flagellaria, Heliconiaceae, Pontederiaceae) and 
some non-commelinoid taxa have non-oblique divisions (e.g. Tecophilaeaceae). Other 
anomalous taxa are irregular (Dioscoreaceae) or with both types occurring (Strelitziaceae 
and Hypoxidaceae). Rasmussen (1983) discussed further developmental patterns in 
monocot stomata, notably the presence of either perigene cells (subsidiary cells derived 
from cells adjacent to the meristemoid) or mesogene cells (subsidiary cells derived 
from the meristemoid), but found little systematic correlation. Our results are therefore 
inconclusive for this character set, which needs further review among other 
monocotyledons to test homologies. 
Cell wall ferulate Following Harris and Hartley's (1980) methods of examination of 
cell wall fluorescence to detect presence of polymer-bound ferulic acid, Rudall and 
Caddick (1994) analysed the taxa of Xanthorrhoeaceae sensit lato. They found positive 
results (ferulates present in cell walls) in Baxteria, Calectasia, Dasypogon, Kingia and 
Xerolirion, and negative results (cell wall ferulates absent) in Acaiithocarpus, 
Chamaexeros, Lomandra, Romnalda and Xanthorrhoea. These results link the former 
group with the commelinoid clade, the latter with the non-commelinoid grade. Chase 
et al. (1995b) found this character to be the most consistent in distinguishing the 
commelinoid taxa from all other monocots. 
