72 Gwynne- Vaughan. — Observations on the 
paper, so many advantages are possessed by the alternative 
term solenostely, that, instead of employing the older word, 
retained by Van Tieghem, it becomes clearly advisable to 
return to the rejected term. The most important of these 
advantages is the complete freedom from that suggestion 
of fusion that is implied by the word gamostely ; and since, 
for the present at any rate, it is intended to use the term 
in a descriptive sense only, as a more convenient expression 
for the closed tubular bundle of De Bary 1 , the absence of 
this idea is a very valuable property of the word. Indeed, 
it becomes an advantage of critical importance when it is 
considered that evidence is forthcpming which renders it 
extremely probable that in most cases no process of fusion 
whatever has anything to do with the production of a soleno- 
stele. As regards the Ferns in particular, it may be safely 
stated that in most cases the solenostelic arrangement of the 
vascular tissue is more primitive than the polystelic, since 
it has been shown in several Ferns that the final polystelic 
condition is preceded by a solenostelic stage at one time or 
another in the life-history of the individual plant. In such 
a plant the solenostele cannot be described as arising from 
the fusion of polystelic steles, but rather the polystelic state 
as brought about by the splitting up of a solenostelic ring. 
However, it is not to be inferred from this statement that 
no cases of real gamostely (in Van Tieghem ’s sense) exist 
at all ; on the contrary, it does not seem by any means unlikely 
that such cases should occur, even among the Ferns them- 
selves, and if future research should bring such a one to 
light, the word gamostely remains ready to hand as a term 
most suitable for the occasion. The fact, however, remains 
that gamostely, as at present applied, is a misleading term, 
because the structure indicated by it has been shown to be 
susceptible of an explanation exactly opposite to that implied 
by the term itself. 
Again, the distinction between solenostely (gamostely) as 
defined by Van Tieghem, and dialystely (polystely with free 
1 Comp. Anat. (Engl, ed.), p. 284, 1884. 
