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Tetopea 9(2): 2001 
All collections cited have been seen unless otherwise indicated. 
Characteristics of the plants 
The characteristics of the plants will be discussed more fully in the paper on 
Australian and New Zealand species. Here, only brief explanations of characters used 
in the key and species descriptions are given. Balslev (1996) gives a useful outline of 
morphological and anatomical characters in the family. 
Culm length is measured from the base of a plant to the lowest involucral bract at the 
base of an inflorescence. This taken together with the inflorescence measurement gives 
an overall size for the plants. Culm diameter has been measured about halfway along 
the length of the culm, as have counts of number of longitudinal striations, and 
assessment of whether the pith is dense or loose, continuous, interrupted or absent, 
and whether septa (transverse or longitudinal) are present. Culm hardness is also 
assessed at that point by compressing the culm with the fingers; culms are often softer 
near their apex than their base. The surface longitudinal striations, which are the 
external reflection of the internal tissue patterns, are useful in separating species in 
section Juncotypus. They are more prominent when the plants are dried. Pith density is 
also characteristic for species in section juncotypus. Density seems to be determined by 
the size of the stellate parenchymatous pith cells and the length of their arms: dense 
pith equating to small cells with short arms and loose pith to bigger cells with long 
arms. Culm colour is useful in discriminating taxa, but that is best assessed from fresh 
material, which has not been seen for all of the taxa dealt with here. 
Leaf blade form and diameter or width are given in descriptions as seen about halfway 
along the lamina unless otherwise indicated. The transverse and longitudinal septa in 
species of section Ozophyllum ( J. leschenaultii, J. sandwithii and J. wallichianus) are more 
obvious in dried specimens, but are best checked by splitting a leaf longitudinally to 
see the interior of the leaf. 'Unitubulose' leaves (Fig. lh) are those with only transverse 
septa (also called 'perfect septa' by some authors), while 'pluritubulose' leaves 
(Fig. lg) have both longitudinal and partial transverse septa ('imperfect septa'). Leaves 
in section Juncotypus consist of a minute mucro-like blade on a well-developed open 
sheath; such leaves are called cataphylls. 
Leaf sheaths are more or less uniformly straw-coloured near the apex of the outer 
surface in all species, hence description of colour refers to the middle and basal 
portions, which range from pale yellowish to dark red-brown externally; all sheaths 
can become blackish in standing water, hi section Juncotypus, the colour of the outer 
(abaxial) and of the inner (adaxial) surfaces of the cataphyll are diagnostic characters 
for a species. The adaxial surface has a whitish pearly sheen in most species, but some 
have darker adaxial surfaces that are darkish golden brown but still often with a 
pearly sheen. Whether the cataphylls in section Juncotypus tightly enclose the base of 
the subtended culm or are loose around it is characteristic for each species. 
Inflorescences are terminal but appear lateral in the section Juncotypus because of the 
well-developed lowermost involucral bract that usually pushes the associated 
inflorescence to one side. Their structure is racemose in subgenus Juncus and cymose 
in subgenus Poiophylli (see discussion and references in Novara (1976) and Balslev 
(1996)), corresponding to the absence or presence of bracteoles under each flower. 
Each branch of an inflorescence is subtended by a bract. The lowermost one or two 
involucral bracts in most species are much larger and more leaf-like in form than those 
higher in the inflorescence (which are often scale-like, and are termed floral bracts when 
they subtend the ultimate inflorescence branches, each bearing a flower). In section 
