62 Transactions. 



that much more fibre, and fibre of better quality, is produced from culti- 

 vated plants. This is due to the fact that millers will not make plantations 

 while the large natural Phormium swamps exist. 



Discussion of Specific Characters. 



There has always been a certain amount of discussion with regard to the 

 number of species in the genus Phormium. Hooker (1853) comes to the con- 

 clusion that there is but one species, but almost all later botanists recognize 

 two- P. tenax and P. Cookianum. In my study of various varieties 1 

 have found that the two species cannot be absolutely separated. After 

 carefully noting the characteristics of each variety, I attempted to put 

 these varieties in some order, and was at once struck by the remarkable 

 continuity of the variation. There is, indeed, a perfect chain of forms 

 more or less closely connected, and the chain is unbroken in passing from 

 " tenax " to " Cookianum '" varieties, for " passage forms " link the two 

 species. That this chain is real will be seen in my classification of varieties, 

 though, no doubt, there are yet many links to be added. However, I 

 decided to group my varieties under the two species now recognized, for 

 the following reasons : — 



In the first place, it will be seen that forms at one end of the chain are 

 vastly different from those at the other end, and this would perhaps warrant 

 the retention of the two specific names, though, of course, this method 

 is wholly artificial. For this I have the authority of Hooker, who, in divid- 

 ing the genus into two species, says at the same time that he considers them 

 to be but " races of one plant." Then, again, 1 have made many attempts 

 to cross-pollinate extreme forms, and have failed to obtain any results. 

 This is certainly an additional reason for retaining the two specific names. 

 The chief differences between two forms, one from each end of my series 

 of varieties, may be taken as the differences between P. tenax and 

 P. Cookianum. These are,— 



(A.) Differences in Vegetative Characters. 



I. Habit. — P. tenax, on the whole, may be said to have an erect habit, 

 though in many varieties the leaves are more or less drooping at the tip. 

 The fans are generally set fairly widely apart, and the leaves clasp one 

 another very closely at the base, this being one of the reasons for the 

 more upright habit. P. Cookianum, on the other hand, has a very drooping 

 habit, the fans are more closely set, and the leaves do not clasp each other 

 closely at the base, but fall apart at a very short distance from the base. 



II. The leaves of P. tenax are stiff and rigid, this being the principal 

 reason, for the erect habit. They are 4-14 ft. long and 2-5| in. broad. 



(a.) The " butt," or clasping sheath-like lower portion of the leaf, is very 

 heavy and long, sometimes being as long as the blade. Its inner surface 

 is more or less brightly coloured, the colour varying from a faint orange- 

 pink to a deep orange. There is generally a fairly large quantity of gum 

 between the two halves of the butt. Very often there is a purple tinge 

 on the outer surfaces at the base. 



(b.) The blade is dark green, the lower surface being glaucous. 



(1.) The apex is obtuse or acute, and in mature leaves the tip is split 

 into two for several inches. 



(2.) The keel is very much thickened on the lower surface, and is brightly 

 coloured with a colour corresponding to that of the margins. 



