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1.
木兰科叶结构的比较解剖及其系统学意义   总被引:6,自引:0,他引:6  
对国产6属11种木兰科植物叶片的结构进行了比较解剖研究。通过比较叶的表皮、皮皮、叶肉及中脉等解剖特征,结果表明:(1)上、下表皮细胞的形态结构在种之间存在差异,(2)下皮存在于木莲属、木兰属、含笑属、合果木属的部分种中,连续或不连续:(3)叶肉中栅栏组织和海绵组织的分化程度以及细胞形态在种间存在差异:(4)中脉维组织具原始怀,维管束环状排列,具髓,外有厚壁细胞组成的维管束鞘包围;维管束的数目在属间  相似文献   
2.
《Journal of Natural History》2012,46(10):1871-1888
The adult medusa of a species of the hydroid genus Hebella Allman, 1888 (family Lafoeidae), with a metagenetic life cycle, is described for the first time. Hebella furax Millard, 1957 is epizoic on other hydroids and releases medusae with four radial canals and three marginal bulbs with tentacles. Adult medusae cultured in the laboratory attained 11 mm in diameter, had 8–11 radial canals, and up to 37 marginal tentacles. Cordyli were present between the tentacles, a characteristic feature of the superfamily Laodiceoidea. The pattern of branching of the radial canals indicates that adult medusae of H.furax should be referred to the genus Toxorchis, possibly to T. kellneri Mayer, 1910.  相似文献   
3.
The hitherto unknown male of Lecane bulla (Gosse, 1851) is described and figured. It is generally similar to the few known males of other Lecane species. However, whereas the degree of fusion of the toes accords between male and female in other species, this is not the case here: the male of L. bulla has two separate and movable toes, these are completely fused into a single toe in the female. This observation further questions the validity of the taxonomic separation of Lecane in three taxa of generic rank, based on the degree of fusion of the toes. The behaviour and reproduction of Lecane is commented upon.  相似文献   
4.
《Journal of Natural History》2012,46(9):1023-1046
Six new species of Nematoplana are described from eastern Australia. They are distinguished on the basis of the morphology of sclerotized structures, chromosome number and morphology, and pigmentation. Six further unguiphorid species were only found immature, and cannot be formally described. They none the less have distinct morphological and/or karyological features. The Unguiphora as a whole, and the genus Nematoplana in particular, are species-rich in eastern Australia. The high diversity of the group appears due both to narrow-range endemics, and to the narrow ecological niche of many of the species.  相似文献   
5.
《Journal of Natural History》2012,46(13):1509-1568
Fifteen species of the genus Symplectoscyphus Marktanner-Turneretscher have been studied, four of which are new to science (Symplectoscyphus anae sp. nov., S. frigidus sp. nov., S. sofiae sp. nov. and S. weddelli sp. nov.). The material studied originates from the Weddell Sea and was collected by several French and German Antarctic expeditions with R.V. Polarstern. Each species is described and figured, the systematic position amongst allied species discussed and available data concerning autecology and geographical distribution given. The type material of five poorly known species of Symplectoscyphus, S. aggregatus (Jäderholm), S. cumberlandicus (Jäderholm), S. glacialis (Jäderholm), S. hero Blanco and S. plectilis (Hickson and Gravely), has been re-examined, re-described and figured. Finally, a general survey of the bathymetrical and biogeographical distribution of the known Antarctic species is given.  相似文献   
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《Journal of Natural History》2012,46(9):1371-1398
The Indo-Pacific species Hypselodoris infucata (Rüppell and Leuckart, 1830) and Hypselodoris obscura (Stimpson, 1855) have been regarded as distinct by most authors. In this paper, numerous specimens with the colour pattern described for both H. infucata and H. obscura, and collected from localities comprising the geographic range of both nominal species, have been examined and anatomically studied. All specimens from south-east Australia, the type locality of H. obscura, consistently have a very long ejaculatory portion of the vas deferens, whereas in specimens collected from other Indo-Pacific localities this portion is very short. There are no other major morphological or anatomical differences between H. infucata and H. obscura. It is not clear whether H. obscura and H. infucata are different species, but since there is at least a consistent anatomical difference between them, they are provisionally regarded as distinct. The reproductive system, radula and external morphology are extremely variable among specimens of H. infucata. Specimens from Indo-Pacific localities other than south-east Australia, even those externally similar to H. obscura, belong to H. infucata. Hypselodoris saintvincentius Burn, 1962, which has been regarded as a synonym of H. infucata, is clearly distinguishable by the external coloration, reproductive system and radular morphology. Phylogenetic evidence indicates that H. saintvincentius is the sister species of H. infucata and H. obscura. A re-examination of the holotype of the uncertain species Brachychlanis pantherina Ehrenberg, 1831 revealed that it is conspecific with Hypselodoris infucata. Therefore, the name Brachychlanis Ehrenberg, 1831, which has not been used for more than 50 years, has preference over the widely used name, Hypselodoris Stimpson, 1855. In order to preserve nomenclatural stability invalidation of the name Brachychlanis is proposed.  相似文献   
9.
From morphological data and polypeptide patterns two species of eugregarine were distinguished in the intestine of the earwig, Forficula auricularia L., in England. One was Gregarina ovata Dufour, 1828 and the other G. forficulae Lipa, 1967 previously reported from Poland.  相似文献   
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