Surface features of the adaxial epidermis in the conduplicate-leaved Cypripedioideae (Orchidaceae)

Epidermal cells from adaxial leaf surfaces of 42 species of Paphiopedilum and 6 species of Phragmipedium were surveyed with the SEM. The surfaces of the cells are flat to papillose and often have various sculpturing patterns. To designate two orders of papilla size the terms 'macropapilla' and 'micropapilla' are proposed. Species exhibiting unornamented flat to macropapillose epidermal cells appear to be correlated with high light environments, whereas those species exhibiting micoropapillae and various degrees of sculpturing appear to be correlated with low light environments. Sculpturing features are often characteristic of a single species, but they may vary considerably between species. Epidermal characters are of some utility in identifying sterile plants which are otherwise indistinguishable.     

A Cytotaxonomic Study on Chinese Dioscorea L.—The Chromosome Numbers and Their Relation to the Origin and Evolution of the Genus

The chromosome numbers of 5 tuberous sections of Chinese Dioscorea, including 23 species and varieties, are reported in the present paper as a continuation of the previous reports. They are all polyploids with the basic number x=10. On the basis of analysis of chromosome numbers of whole genus, the rhizomatous diploid species of Sect. Stenophora Uline are presumed to be primitive taxa, while the polyploids of chromosome numbers 40-142 are considered derived groups as a result of hybridization between their ancestral diploids followed by chromosome doubling. Sect. Lasiophyton Pr. et Burk., Sect. Opsophyton UIine, Sect. Shannicorea Pr. et Burk., Sect. Combilium Pr. et Burk. and Sect. EnantiophylIum Uline may be the advanced groups. The chromosomal evolution and geographical distribution suggest that the primitivediploid might have originated in Hengduan Mountains of Asia, an old highland.     

On Paphiopedilum malipoense sp. nov.—An Intermediate Form Between Paphiopedilum and Cypripedium,with a Discussion on the Origin of the genus

Paphiopedilum malipoense S. C. Chen et Tsi is a very interesting new species with its flower similar to that of Cypripedium, especially section Cypripedium. It belongsto subgenus Brachypetalum, the most primitive group of Paphiopedilum, but differs fromits allied species in hgniva elliptic-lanceolate sepal with cuspidately acuminate apex, rathernarrow petals and horizontal lip, which are of common occurrence in many cypripediums, butvery rare in paphiopedilums. Apparently, this is an intermediate form, or a link, betweenPaphiopedilum and Cypripedium, but it does not seem to arise from hybridization betweenthem, because no Cypripedium has been found wherever Paphiopedilum occurs. The new species is distributed in southeastern Yunnan of China. In this area, as wellas in river valleys of western Yunnan or the Hengduan Mountains, there have been fourspecies of the same genus reported before. As we know, the Hengduan Mountains and theiradjacent areas are rich in Cypripedium. The differentiation of the genus there is remarkable. All five sections it contains occur there and three of them are quite distinctive. Forexample, the general appearance of the section Bracleosa is dissimilar to that of any othercypripediums, but closely resembles that of Listera. It appears that the difference betweensect. Bracteosa of Cypripedium and sect. Brachypetalum of Paphiopedilum is not necessarily wider than that between sect. Bracteosa and sect. Cypripedium of the same genus.Apparently, it is reasonable to consider Paphiopedilum to be an evolutional branch of Cypripedium extending into tropical area, with its primitive group (subgenus Brachypetalum)still remaining in its northern fringe area. This primitive subgenus has eight species, distributed from western Yunnan to the Malay Peninsula. Five of them, including the intermediate and primitive form published here, are found in the hilly land of southeastern Yunnan and the river valleys of western Yunnan. All these facts suggest its area of origin: theriver valleys of the Hengduan Mountains and the lower hilly land contiguous to the southof them.     

Pollination of Cypripedium plectrochilum (Orchidaceae) by Lasioglossum spp. (Halictidae): the roles of generalist attractants versus restrictive floral architecture

The pollination of Cypripedium plectrochilum Franch. was studied in the Huanglong Nature Reserve, Sichuan, China. Although large bees (Bombus, Apis), small bees (Ceratina, Lasioglossum), ants (Formica sp.), true flies (Diptera) and a butterfly were all found to visit the flowers, only small bees, including three Lasioglossum spp. (L. viridiclaucum, L. sichuanense and L. sp.; Halictidae) and one Ceratina sp., carried the flower's pollen and contacted the receptive stigma. Measurements of floral architecture showed that interior floral dimensions best fit the exterior dimensions of Lasioglossum spp., leading to the consistent deposition and stigmatic reception of dorsally-placed, pollen smears. The floral fragrance was dominated by one ketone, 3-methyl-Decen-2-one. The conversion rate of flowers into capsules in open (insect) pollinated flowers at the site was more than 38%. We conclude that, while pigmentation patterns and floral fragrance attracted a wide variety of insect foragers, canalization of interior floral dimensions ultimately determined the spectrum of potential pollinators in this generalist, food-mimic flower. A review of the literature showed that the specialised mode of pollination-by-deceit in C. plectrochilum, limiting pollinators to a narrow and closely related guild of 'dupes' is typical for other members of this genus.     

杓兰属(兰科)中一个国产种类的新等级

丽江杓兰大围山变种(Cypripedium lichiangense vat．daweishanense)被提升为种的等级：大围山杓兰(Cypripedium daweishanense)。此种的特征是：中萼片浅黄绿色,上面疏被栗色斑点;花瓣较短,近等长于或略长于唇瓣。而丽江杓兰(Cypripedium lichiangense)的中萼片为紫肝色;花瓣要长得多,大约为唇瓣长的2倍。它们均属于三棱组(Cypripedium sect．Trigonopedium)。该组共含11种,均为中国特有种。文中提供了一个该组的分种检索表。     

应用ITS序列分析探讨偏花报春的系统位置

对于偏花报春Primula secundiflora Franch. 的系统位置,主要有两种意见,一种认为偏花报春具有典型的钟状花冠,应置于钟花报春组Sect．Sikkimensis;而另一种意见则依据其他特征将其置于灯台报春组sect．Proliferae。通过对偏花报春、灯台报春组4种植物和钟花报春组3种植物核糖体DNA中的内转录间隔区(ITS)的序列测定及分析,并结合形态学及染色体特征的比较论证,认为偏花报春应置于灯台报春组。     

杓兰属(兰科)中一个国产种类的新等级(英文)

丽江杓兰大围山变种(Cypripedium lichiangensem var.daweishanense)被提升为种的等级:大围山杓兰(Cypripedium daweishanense)。此种的特征是:中萼片浅黄绿色,上面疏被栗色斑点;花瓣较短,近等长于或略长于唇瓣。而丽江杓兰(Cypripedium lichiangense)的中萼片为紫肝色;花瓣要长得多,大约为唇瓣长的2倍。它们均属于三组(Cypripediumsect.Trigonopedium)。该组共含11种,均为中国特有种。文中提供了一个该组的分种检索表。     

20种山茶属连蕊茶组和毛蕊茶组植物的花粉形态特征研究

通过开展山茶属连蕊茶组（Camellia Sect. Theopsis）和毛蕊茶组（Camellia Sect. Eriandria）的花粉形态研究,为2组植物的系统演化、分类鉴定等提供一定的参考依据。以2组植物的20种（变种）材料为研究对象,进行花粉形态的扫描电镜观察。结果显示：（1）20种连蕊茶组和毛蕊茶组植物主要为中等花粉（25~50 μm）和大花粉（50~100 μm）,花粉极面观为三裂圆形,赤道面观为长球形,萌发孔类型为3孔沟型。（2）花粉的外壁纹饰主要包括孔穴状、疣状和颗粒状3种纹饰类型,长管连蕊茶（C. elongata）为孔穴状纹饰,蒙自连蕊茶（C. forrestii）和尖萼蒙自连蕊茶（C. forrestii var. acutisepala）为疣状纹饰,其余17种（变种）均为颗粒状纹饰。研究推测2组植物花粉外壁纹饰的演化趋势为孔穴状→颗粒状→疣状。花粉的形态特征支持连蕊茶组和毛蕊茶组植物为单系类群的观点,但作孚连蕊茶（C. tsofuii）和荔波连蕊茶（C. lipoensis）作为变种的分类观点有待进一步研究探讨。     

中国马尾杉属(石杉科)的两个组

本文记述了中国产马尾杉属Ｐｈｌｅｇｍａｒｉｕｒｕｓ（Ｈｅｒｔｅｒ）Ｈｏｌｕｂ的两个组,即龙骨组（新组合）ｓｅｃｔ．Ｃａｒｉｎａｔｕｒｕｓ（Ｈｅｒｔｅｒ）Ｈ．Ｓ．Ｋｕｎｇ ｅｔ Ｌ．Ｂ．Ｚｈａｎｇ和马属组ｓｅｃｔ．Ｐｈｌｅｇｍａｒｉｕｒｕｓ。确认这两组在中国共８种,分别编写了两组的分种检索表及各种的地理分布,并提出一个新异名：Ｐｈ．ｃａｍｃｅｌｌａｔｕｓ ｖａｒ．ｍｉｎｏｒ（＝Ｐｈ．ｃａｎｃｅｌｌａ