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71.
石铸 《中国科学院研究生院学报》1987,25(3):189-203
After having examined all specimens of the genus Prenanthes L. of Compositae in
the Herbarium of Institute of Botany, Academia Sinica, I find that the classic concept on the
genus Prenanthes established by G. Bentham in 1873 has not been held exactly by some of Euro-
pean, American, Japanese and Chinese botanists. For example, W. B. Hemsley, S. T. Dunn, A.
Franchet, S. Kitamura and C. C. Chang placed plants from China which belong to other groups
into the genus; I also find that the classic concept of the genus is not clear. The present paper
makes a revision not only on the classic concept of the genus, but also on its concept assumed by
the above-mentionded botanists.
With the combination of numerous (25-35), white or yellow ligular florets, numerous ribs
of achenes, Prenanthes alba L. (Nabalus albus (L.) Shih, comb. nov.) is distinctly different
from Prenanthes purpurea L., which has the combination of purple, few (5-15) ligular flo-
rests and few ribs of achenes. Nabalus Cass., as a genus established early (1825) by H. Cassini,
should be restored. It is not reasonable to treat Nabalus as a subgenus (E. B. Babcock et al.
1947) or a section (S. Kitamura, 1956) or as a synonym (G. Bentham, 1983) of the genus
Preanathes L.
The present author recognizes seven species in the new revised genus Prenanthes L. in
China, 4 of which are described as new. In the genus Nabalus Cass. only one species, N.
ochroleuca Maxim., is distributed in Northeast China.
As Lactuca melanantha Franch. (1895), Prenanthes henryi Dunn (1903), P. glandulosa
Dunn (1903), Lactuca triflora Hemsl. (1888) (it was transferred to Prenanthes L. by C. C.
Chang in 1934), Prenanthes formosana Kitam. (1934) and P. wilsoni Chang (1934) all have
campanulate involucres, purple phyllaries, purple dorsi-ventrally compressed achenes, longitu-
dinal rids 6-9 on each side of achene truncate and beakless at its apex and pilose tubes of co-
rollae, they should be placed neither into the genus Prenanthes with obtusely tri-or pentagonous,
subterete achenes and glabrous tubes of corollae, nor into the genus Lactuca with beak achenes.
Besides the above-mentioned species misnamed by some of foreign and Chinese botanists, 6 other
species also have the same structure in achenes and corollae. Evidently, they fall into a new
genus with the name Notoseris Shih.
The new genus Notoseris Shih of the tribe Lactuceae of Compositae seems to be more re-
miniscent of Lactuca L. than of Prenanthes L. emend.
All the 12 species of the genus Notoseris Shih are endemic to China and distributed in the
area of south of Yantze River. Of them 6 are new combinations and 6 are described as new. 相似文献
72.
石铸 《中国科学院研究生院学报》1991,29(5):394-417
本文是对中国-喜马拉雅地区的原莴苣属植物提出的分类订正。是笔者前一篇文章《莴苣属订正
及亚洲大陆菊科植物二新属》的续篇。文中建立了两个新属,即毛鳞菊属Chaetoseris Shih和细莴苣属Stenoseris Shih;文末及文中提供了本文所涉及的一些属种的分属和分种检索表。 相似文献
73.
石铸 《中国科学院研究生院学报》1988,26(6):418-428
Having mixed extremely various patterns of achenes for a long time in
the genus Lactuca L., especially showed in the classification of it on the mainland of Asia,
Lactuca L., the primary unnatural genus, becomes more nuclear in its limit. The present
paper makes a revision to attempt providing a clear cline between Lactuca L. and its relative
genera.
On my opinion, only plants, represented by Lactuca sativa L., which have ovoid capitu-
lum during its fruiting, numerous (7-25), yellow ligular florets and longitudinal 1-10 ribs
or striae on each side of achenes, acute into filiform beak at its apex, should be defined as
Lactuca L.
In view of the present concept of Lactuca L., another group of plants, embodied by
Lactuca indica L., having its broadening, thin winged-margin of, 1-3 striae on each side of
achenes, black, dorsi-ventral compressed, acute into thick and short beak at its apex, evident-
ly, should not be placed into Lactuca L., but be regarded as genus, i.e. Pterocypsela Shih,
gen. nov. Pterocypsela Shih distributes in Eastern and southern Asia, where Lactuca L. does
not occur. In China there is all of species, seven species, of Pterocypsela Shih. They are P.
raddeana (Maxim.) Shih, P. indica (L.) Shih, P. elata (Hemsl.) Shih P. lacciniata (Houtt.)
Shih, P. triangulata (Maxim.) Shih, P. sonchus (Lévl.) Shih and P. formosana (Maxim.)
Shih, But in Mediterranean regions and Middle and Western Asia mainly distributes Lactu-
ca L., in which there are only seven species from western China, Xijiang autonomic district.
They are L. dolichophylla Kitam., L. sativa L., L. altaica Fisch. et Mey., L. serriola Torner,
L. dissecta Don, L. auriculata DC. and L. undulata Ledb.
With the combination of violet-purple ligular florets non-ovoid capitulum during its
fruiting, a little thick achenes, acuminate into longer. or short beak at its apex and 4-6 ribs
on each side of it, Mulgedium tataricum (L.) DC. is evidently different from Lactuca sativa L.
with combination of ovoid capitulum during its fruiting, yellow ligular florets and compres-
sed achenes, acute into filiform beak at its apex. There seems to be no point in refusing Mu-
lgedium Cass. as a genus. Strictly speak, Mulgedium Cass. seems to be reminiscent of Para-
prenanthes Chang (see bellow) without beak at the apex of its achenes. In Hengduan moun-
tains and mountain range of Himalayas M. tataricum (L.) DC. discoveries its relative par-
tners. They are M. bracteatum (Mook. f. ex. C. B. Clarke) Shih, M. lessertianum (Wall. ex
C. B. Clarke) DC., M. monocephalum (Chang) Shih, M. umbrosum (Dunn) Shih, M. meridi-
onale Shih and M. polypodifolium (Franch.) Shih.
Having broadering and thickening margin and 4-7 striae on each side of achenes, grey,
dorsi-ventral compressed, truncate and beakless at its apex, Lactuca sibirica (L.) Benth. ex
Maxim. (Sonchus sibiricus L.) is not only different from Lactuca sativa L. with the combi-
nation of yellow ligular florets and filiform beak at apex of its achenes, but also from the
genus Mulgedium Cass. with beak at apex of its achenes. Therefore, Lagedium Sojak, establi-
shed by J. Sojak (1961), should be restored. It should be point out that Lagedium Sojak is
monotypic genus excluding Mulgedium tataricum (L.) DC. with beak at the apex of its ache-
nes, non-marginated. Lagedium Sojak widely distributes in temperate and frigid zone of
northern hemisphere. In our country, Lagedium sibiricum (L.) Sojak, sole species of the ge-
nus, restricts its northeast region.
Paraprenanthes Chang, the new genus, established by Ch. Ch. Chang (1950) based on La-
ctuca sororia Miq. and Lactuca yunnanensis Franch. seems to be a distinct genus. This ge-
nus is characterized by 4-6 ribs on each side of achenes, black, fusiform, a little thick and
beakless at its apex. Besides above-mentioned two species, assigned by Chang, in forest of tro-
pic and subtropic zones on the mainland of Asia there are many species with same structure
in achenes like L. sororia Miq. and L. yunnanensis Franch. The genus Paraprenanthes Chang
seems to be reminiscants of Mulgedium Cass. and Lagedium Sojak, but differs from the former
in its beakless achenes, from the later in its non-marginated achenes and 4-6 ribs on each
side of it. In our country, there are all species of the genus known in the tropic and sub-
tropic zones on the mainland of Asia. They are P. sororia (Miq.) Shih, P. yunnanensis (Fra-
nch.) Shih, P. longiloba Ling et Shih, sp. nov., P. heptontha Shih et D. J. Liou, sp. nov., P.
prenanthoides (Hemsl.) Shih, P. pilipes (Migo) Shih, P. thirionii (Lévl.) Shih, P. sylvicola
Shih., sp. nov., P. multiformis Shih, sp. nov., P. auriculiformis Shih, sp. nov. and P. sagitti-
formis Shih, sp. nov. 相似文献
74.
石铸 《中国科学院研究生院学报》1988,26(5):382-393
本文是对菊科莴苣属Lactuca L. 的分类订正, 文中起用了乳苣属Mulgedium Cass.和山
莴苣属Lagedium Sojak两个较老的属名, 建立了二个新属,即翅果菊属Ptrocypsela Shih与假
福王草属Paraprenathes Chang. 文末提供了莴苣属及邻近属以及东亚地区的有关种类的分属分种检索表。 相似文献
75.
76.
77.
78.
79.
This study presents a novel approach to decant supernatant on a centrifugal platform. By manipulating the centrifugally induced pressure and the elastic deformation of the plastic lids in the decanting chamber, fixed amounts of the supernatant can be decanted into the detection chamber at lower rotational speeds. The experimental results showed that decanted volume is affected by the volume of deformation and the operating parameters. Factors that influence the decanting ratio are also discussed. This approach has the advantages of simple design and low manufacturing cost; further, it has no need of surface modification. It has been applied to on-disk separation of plasma from whole blood, and the results showed good stability and repeatability. 相似文献
80.
SUNG Wen-pei SHIH Ming-hsiang LIN Cheng-I GO Cheer Germ 《浙江大学学报(A卷英文版)》2005,6(8):878-885
INTRODUCTION The conventional design of rails uses steel clipboards and bolts to link rails, and avoids bucklingcaused by thermal expansion effect by mountingexpansion joints to solve axial restraint generated byseasonal or day-and-night temperature changes. Butthe discontinuity at the rail joints brings discomfortand noise to passengers when the train has suddenlystops or starts, during which train speed cannot beeffectively increased, rails are more easily damaged,and the cost of mainte… 相似文献