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L. Cockayne 
red drupes and the var. with them white. On the other hand, there 
are drupes of many shades of blue passing into translucent white in 
Coprosma brunnea. 
Agropyron scabrum is defined in the Manual , p. 923, as " annual 
or perennial, very variable.’’ Usually it is found growing as a 
straggly grass with one or two long culms in the dense tussocks of 
Festuca novez-zelandice or Poa ceespitosa, in the low tussock-grass¬ 
land. But where ground is fenced from stock for a few years this 
grass has assumed its true forms. These are of two classes, the one, 
a true tussock, and the other, of much more open and lower growth 
and spreading considerably by means of underground stems. But 
the polymorphy does not end here, for leaves varying both in breadth 
and hue occur on different individuals and there are also many 
individual differences in the length of the fruiting stems, the number 
and size of the spikelets and the length of the awns. There are also 
apparently narrow-leaved and broad-leaved races. These various 
characters—tussock, turf-like, leaves broad or narrow and of various 
colours, and floral distinctions—are almost certainly marks of 
varieties, and their combinations denote hybridism. 
In some cases well-defined varieties occur which are of more or 
less local distribution, and at the limits of their areas, or of their 
particular habitat, hybridise with a more wide-spread variety. Thus 
Veronica salicifolia var. longeracemosa —a shrub more or less common, 
and perhaps the sole representative of the species in a certain part 
of the Egmont-Wanganui Botanical District, at the eastern boundary 
of its domain crosses with another var. of the same species. More 
striking are the many intermediate forms which occur when the 
swamp-dwelling V. salicifolia var. paludosa of the Western Botanical 
District crosses with the ubiquitous V. salicifolia var. communis. 
Much more complex than the cases cited above is that of Aceena 
Sanguisorbce. This aggregate gives rise to a remarkable variety of 
forms. Certain clear-cut varieties have been defined, e.g. viridior, 
pilosa , sericei-nitens and minor (this confined to the Subantarctic 
Islands and invariable). Viridior occurs side by side with the 
wide-spread var. pusilla (possibly an aggregate) and they may occa¬ 
sionally cross. Pilosa and sericei-nitens often occur pure in the 
mountains over considerable areas, but meeting var. pusilla much 
crossing takes place. The polymorphy becomes still more marked if 
varieties of Accena inermis or microphylla are present, for these 
readily join in the crossing. Finally, if A. novce-zelandice is present 
still more forms will arise. 
