108 PROF. T. H. HUXLEY ON THE GENTIANS. 
type which I shall describe under the head of Lissanthe; and 
in Gentiana lutea in the direction of Piychanthe. The spa- 
those calyx and the ovary of Gentiana lutea present points of 
strong resemblance to those of G. purpurea ; and the free hybri- 
dization, under natural conditions, ofthe two last-mentioned spe- 
cies is asserted upon apparently strong evidence. In my opinion, 
however, that evidence is by no means so conclusive as it looks 
at first sight ; and the facts of the case require careful and expe- 
rimental re-examination. ` 
It is of course possible that @. lutea may be an ally of @. pur- 
purea which has reverted to a less modified condition; but at 
present I see no sufficient grounds for adopting that hypothesis. 
VI. Limnanthe. 
The corolla is rotate and devoid of nectaries. The margins of 
the lobes may be laciniated ; or their surfaces may be beset with 
longitudinal rows of fimbrie (Menyanthes). Five, apparently 
glandular “ hypogynous” tubercles are commonly developed at 
the junction of the walls of the ovary with the perianthial cup, 
which is more or less adherent to the base of the ovary. 
A. B. . OC 
Menyanthes. 
imnanthemum. Limnanthemum. Limnanthemum. 
7 => . Villarsia. 
D. E. 
Liparophyllum. Liparophyllum. 
Limnanthemum. : = 
Villarsia. 
All systematic botanists recognize the aberrant character of 
the Menyanthee. But I do not find in the works which I have 
consulted any notice of the circumstance that some of them, at 
any rate, present a more or less marked perigyny. I have exa- 
mined only Limnanthemum indicum, Menyanthes trifoliata, Yil- 
larsia capensis, and Liparophyllum Gunnii; but in all these the 
perianth adheres to the base of the ovary, and the adhesion 
becomes more and more extensive in the order in which the spe- 
cies have been named. 
VII. Lissanthe. : 
: The corolla is devoid of nectaries. Sometimes there are dis- 
tinct, apparently nectarial tubercles on the base of the ovary; 
