478 OPHIOGLOSSALES 
affected by disturbed nutrition. This may be presumed to have been the 
case in Pszlotum, where the large size of the synangium proportionally to 
the small bifurcate leaf indicates reduction of the latter, but not of the 
former in the same degree. 
In estimating the effect of mycorhiza in any family as a whole in which 
it occurs it is necessary to take into account in the first place its constancy; 
and it is seen that it is not constant in the Ophioglossaceae. Secondly, 
it-is a matter of general observation that plants with an endotrophic 
mycorhiza commonly show a structure in accordance with a limited tran- 
spiration stream: their root-system is compact, and hydathodes are absent 
from their rather leathery foliage! The Ophioglossaceae show such 
structure, which should not be confused with the results of saprophytic 
reduction. It may have been primitive for them, and in this connection 
it is to be noted that mycorhiza has been described in plants from the 
Lower Coal Measures, so that it is no newly adopted manner of life.? 
The condition of elminthostachys, with its mycorhizal embryo and non- 
mycorhizal mature plant, would be consistent with a primitive mycorhizal 
state, from which the plant had broken loose and passed to an autotrophic 
condition. But, thirdly, it is important to note that among plants at large 
many species in which it is present show no sign of reduction either in 
their vegetative or in their reproductive parts. This may be well illustrated 
among the Pteridophytes themselves. Thus Lycopodium inundatum is found 
to be mycorhizic, but its general habit, especially in the large American 
forms, does not suggest reduction as compared with other species. 
L. cernuum is mycorhizic in the young plant, but it is one of the most 
elaborate of Lycopods. Selaginella spinulosa is mycorhizic, but S. helvetica 
is not; and yet S. sfznulosa cannot be held as relatively reduced. How 
little the occurrence of mycorhiza may be found to affect the morphological 
character of Ferns is*shown in the Marattiaceae. According to Kiihn® 
a fungus is found in the roots of Kawulfussta, of Angéopteris, and of 
Maratha alata, but not in those of Marattia fraxinea; but no reduction 
is to be noted as the result in the former Ferns as compared with the 
latter. Again, Cyathea is stated to have mycorhiza, while Asplenium nidus 
has not.4| Such facts as these clearly indicate that in Pteridophytes the 
presence of a mycorhiza does not spell reduction. Accordingly it cannot 
be justly assumed that the somewhat inconstant occurrence of the mycorhizic 
habit in the Ophioglossaceae has been a source of general reduction in the 
family, though reduction may have played its part in certain species. The 
argument in favour of their being a reduction series as a whole will have 
to be based on other evidence. 
Pending the statement of such evidence, the Ophioglossaceae may be 
treated, without any preconceived idea of general reduction, in the same 
way as any other family of plants. The natural comparison of them 
1Stahl, Zc. 2 Weiss, Ann. of Bot., xviii, p. 255. 
% Flora, 1889, pp. 491-497. 4 Janse, /c., p. 64. 
