372 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
the lower and most sensitive part of the filament ( Opuntia ) ; (2) Cyna - 
raceme-type : the five syngenesious stamens are epipetalous, the filaments 
are sensitive on all sides and for their whole length ; when at rest they 
are curved outwards ; when irritated they contract and become nearly 
straight ; the contractile tissue penetrates the whole of the filament 
(many Composite) ; (3) Cistinese and Mesembryanthemaceae-type : the 
numerous free filaments are sensitive on all sides, but most so on the 
outer side ; when irritated they bend centrifugally towards the corolla 
(Helianthemum, Cistus, Mesembryanthemwn) ; (4) Tiliaceae and Portu- 
lacacese- type : the numerous filaments are sensitive on all sides, but 
chiefly on the outer side, and become concave on the irritated side 
(i Sparmcinnia , Portulaca) ; (5) Berberideae-type : the six free filaments 
are sensitive only on the inner side, and only immediately above their 
insert’on and immediately beneath the anthers; the curvature is centri- 
petal and brings the anther into contact with the stigma ( Berberis , 
Mahonia). 
There is, on the other hand, no such difference in the structure or 
in the seat of the sensitiveness in irritable stigmas ; they are found in 
the orders Scrophulariaceae, Pedalineae, Acanthacese, Bignoniacese, and 
Capparidese. 
A list is appended of those species in which the flower opens only 
once and then closes, and of those in which it opens and closes more 
than once. 
In a subsequent communication * Dr. Hansgirg adds considerably to 
the list, and enumerates other examples of types (l)-(4). To type 
(4) belong several species of Abutilon , but sensitive stamens or stigmas 
were not observed in any other plants belonging to the Malvaceae. 
The author adds further remarks on the flowers which he terms 
“ pseudo-cleistogamic,” i. e. those which resemble the ordinary flowers in 
every respect except that they do not open, and are self-fertilized ; pre- 
senting thus an intermediate condition between ordinary and truly 
cleistogamic flowers. A list is appended. 
Nyctitropic Movements of Leaves. f — Prof. A. Hansgirg enumerates 
a large number of species of flowering plants which display nyctitropic 
movements of the leaves or leaflets, in which the phenomenon had not 
previously been recorded. As in the case of carpotropic, so with nycti- 
tropic movements, it is not uncommon for nearly allied species to differ 
from one another in their presence or absence. The author arranges 
the genera in which the leaves display conspicuous nyctitropic, frequently 
accompanied by sensitive, movements, under a number of types, the 
primary distinction depending on the presence or absence of motile 
cushions at the base of the leaf or leaflet. 
Carpotropic Curvatures of Nutation. — By this term Prof. A. 
Hansgirg designates those movements of the fruit-stalk, or of the sepals 
or bracts, which are designed for the protection of the ripe fruit, or to 
promote the dissemination of the mature seeds. They are not so de- 
pendent on the daily alternations of temperature as are the gamotropic 
* Op. cit., xlv. (1891) pp. 70-5. 
t Ber. Deutsch Bot. Gesell., viii. (1890) pp. 355-64. Cf. this Journal, 1890, 
p. 484. J Ber. Deutsch. Bot. Gesell., viii. (1890) pp. 345-55. 
