椭圆斜羽叶的解剖研究及斜羽叶的系统分类位置

本文根据对椭圆斜羽叶(Plagiozamites oblongifolius)钙质石化化石的研究,认为其主要特征如下:羽状复叶,叶肉无海绵组织和栅栏组织分化。羽片叶脉维管束外韧式,木质部外始式,与现代苏铁属叶脉特征相近。羽轴维管束为“U”形,外始式木质部、梯状纹孔管胞,与现代苏铁属的羽轴维管束相似。根据上述特征,目前可将斜羽叶属归入原始苏铁类植物。但是,如果斜羽叶的生殖器官同 Noeggerathia 一样,为异孢型孢子囊穗,则斜羽叶可能为一种与苏铁类起源有关的原裸子植物。     

On the systematic position of the family Gyrinidae (Coleoptera: Adephaga)

Various characters of adult and larval members of Adephaga and Cupedidae were analyzed, and suggest that Gyrinidae are the sister-group of the remaining Adephaga, and are not closely related to the remaining aquatic Adephaga. The aquatic families Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae seem to form a well founded monophyletic unit. The following characters are considered as synapomorphies of Adephaga excluding Gyrinidae: bifurcate condition of the muscle (= M.) tentoriopraementalis inferior, reduction of hypopharynx, strongly developed prosternal process, reduction in size and specialized modification of the ventral sclerite of the mesothorax, strongly developed mesofurcal arms, a high mesopleural ridge, globular mesocoxae restricted to rotatory movements, invaginated sternum VIII (coxostemum), the strongly curved base of the median lobe of the aedeagus, which articulates with the parameres, the rotated position of the aedeagus in repose, fusion of the larval clypeolabrum with the frons and reduction of the larval lacinia. Mesal shifting of M. episterno-coxalis prothoracis, and the fusion of the apical portions of the malpighian tubules of either side are considered as synapomorphies of Adephaga excluding Rhysodidae and Gyrinidae. Lateral reduction of the meta “sternal” transverse ridge and the presence of the subcubital setal binding patch of the hind wing are considered as synapomorphic characters of Trachypachidae, Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae. We postulate that the metacoxal fusion occurred independently in gyrmids and the common ancestor of Trachypachidae, Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae. Consequently we consider this character state as another synapomorphy of Trachypachidae and Hydradephaga excluding Haliplidae and Gyrinidae. The following characters are considered as synapomorphies of Noteridae, Amphizoidae, Hygrobiidae and Dytiscidae: Loss of tactile setae on the head capsule, metafurcal origin on the intercoxal wall, expansion of the intercoxal wall, elongation of the subcubital setal binding patch, loss of Mm. furca-coxale anterior and posterior, reduction of the larval abdominal segments IX and X, and the shifting of the uropmphi onto the ventral side of segment VIII. Presence of M. tentorio-mandibularis and M. stipitopalpalis intemus are certainly primitive features of adult gyrinids but the distribution of these character states among most members of Adephaga is yet unclear. Chemical defence gland constituents point towards a very isolated position of Gyrinidae. The old age of the group, documented by a larva found in upper Permian deposits, may support the hypothesis of a sister-group relation-ship between Gyrinidae and the remainder of Adephaga.     

Autecological investigations on marine diatoms. 5:Coscinodiscus concinnus W. Smith andRhizosolenia setigera Brightwell

The cold oligo-eurytherm diatomsCoscinodiscus concinnus W. Smith andRhizosolenia setigera Brightwell were cultured to determine their best competitive position by growth. Comparison of their generation times with those of other diatoms indicate that they reach this position between 6°C and 12°C. Both species grew between –1.5°C and about 20°C. The experiments indicate thatC. concinnus flowerings are possible in a deep water column, during periods of high light intensities. The simultaneous death of species in the upper layer is also caused by high light intensities.C. concinnus appeared in two morphological forms; the normal voluminous form, and a flatter form with a few intercalary bands only, filled with large oil-droplets. The latter appeared at 0°C and below, and at the upper temperature limit for growth of about 19°C–20°C. The separation of nov. spec. fromC. concinnus based on the absence or presence of a hyaline area and intercalary bands as identification characteristics should be reconsidered.     

Waterstriders (Gerris paludum F.) compensate for drift with a discontinuously working visual position servo

Waterstriders on ponds and creeks compensate for displacement caused by wind or water current with periodical jumps against the direction of drift. This behavior is mediated by visual stimuli.

The social position of male Barbary macaques (Macaca sylvanus) in a semifree-ranging population

A study was carried out on the social position of 12 subadult males of a semifreeranging Barbary macaque population during the non-mating season. The social position was measured in terms of spatial as well as interactive parameters. The subadult males had social contacts to members of nearly all other age-sex classes but showed clear preferences for same-sexed partners. Besides this differences were found between 5- and 6-year-old males with respect to their interaction profiles and the preference for special classes of interaction partners. The terms “peripheral-central” is discussed with reference to the social structures of macaque societies. The data of the present study indicate that the social position of subadult male Barbary macaques can not be described by one of these terms exclusively. The results are compared to other studies on Barbary macaques and other macaque species. It is concluded that in macaque societies subadult males are not obligatorily forced to live at the periphery or to abide. It is proposed not to postulate stiff social structures but to put more emphasis on the range of variation among macaque species.     

金钱松（属）的细胞分类学研究

我国特有植物金钱松Ｐｓｅｕｄｏｌａｒｉｘａｍａｂｉｌｌｓ的体细胞染色体数目为２ｎ＝４４,不同于ｎ＝１２（Ｍｉｙａｋｅ＆Ｙａｓｕｉ,１９１１）和２ｎ＝２４（Ｄｕｎｉｅｕ－Ｖａｂｒｅ,１９６１）的结果。核型公式为Ｋ（２ｎ）＝４４＝４ｓｍ＋４０ｔ）４ＳＣ）属３Ｂ类型,与Ｋ（ｎ）＝２２＝２ｍ＋２０ｔ（Ｓａｘ＆Ｓａｘ,１９３３）和Ｋ（２ｎ）＝４４＝４ｓｍ＋４０ｔ（Ｈｉｚｕｍｅ１９８８）有差异。染色体相对长度组成为＝４４＝４Ｌ＋１２Ｍ＿２＋２６Ｍ＿１＋２Ｓ。金钦松（属）不仅在染色体数目（２ｎ＝４４）和核型（具２０对端着丝粒染色体）而且它的一些形态、解剖学和植化性状与所有松科其它各属不同。另外,它的一系列形态、解剖、孢粉、生化、植化和古植物学特征显然表明把该属与落叶松属、雪松属一起组成落叶松亚科是不适宜的。因此似乎有理由把金钱松从该亚科分出并建立一个单型的金钱松新亚科。本文还对金钱松（属）核型可能由近缘的铁杉属起源和进化而来作了讨论。     

伯乐树茎次生木质部结构的研究

利用光镜和扫描电镜对伯乐树（Ｂｒｅｔｓｃｈｎｅｉｄｅｒａ ｓｉｎｅｎｓｉｓＨｅｍ ｓｌ．）茎次生木质部的结构进行了研究。其主要特征为：（１）散孔材,有较明显的生长轮;（２）导管分子多为单穿孔板,少数为梯形复穿孔板,具螺纹加厚;（３）管胞、纤维－管胞和韧型木纤维同时存在,后两者有的具分隔;（４）木薄壁组织以轮界分布为主;（５）木射线多为大型异形射线,属异形ＩＩＢ型;（６）缺乏侵填体、树脂道及分泌细胞。对伯乐树科（Ｂｒｅｔｓｃｈｎｅｉｄｅｒａｃｅａｅ）的系统位置作了探讨。     

Fluorescence and reflectance characteristics of manganese deficient soybean leaves: Effects of leaf age and choice of leaflet

Leaf reflectance and fluorescence characteristics of soybean (Glycine max cv Bragg) are influenced strongly by Mn availability. This report evaluates the effects of leaflet choice, leaf age, and leaf nodal position on several spectral characteristics. Leaves were obtained from soybeans grown hydroponically under controlled environmental conditions with wide differences in Mn supply. The ratio of constant yield fluorescence (F_o) to variable yield fluorescence (F_v), the ratios of reflectance at 750 nm to 550 nm and that at 650 nm to 550 nm, the position of the "red edge" near 700 nm, and an index of leaf "yellowness" were measured periodically. Increasing leaf age caused increases in the "red edge" and in both reflectance ratios. Leaf "yellowness" and the fluorescence ratio F_o/F_v decreased with leaf age and increased with leaf nodal position, primarily in Mn deficient leaves. Effects arising from leaf choice were smaller than those caused by Mn deficiency.     

Isolation of a new paramutagenic allele of thesulfurea locus in the tomato cultivar Moneymaker following in vitro culture

A new allele, SC148, of thesulfurea locus inLycopersicon esculentum was detected in a line derived after repeated selfing of plants that had been regenerated from tissue culture. Like the originalsulf mutant, SC148 displayed two mutant phenotypes: green-yellow speckled plants in which thesulf ^vag allele is present and pure yellow plants homozygous for thesulf ^tpura allele. Although the mutant alleles are recessive to wild-type, an unpredictable number of variegated and pura plants appeared in F₁ progenies that had been derived from crosses between SC148 and wild-type tomato plants. The presence of the wild-typesulf ⁺ allele in these variegated heterozygotes was demonstrated using a cytological marker that is linked tosulf. It is concluded that the mutantsulf allele of SC148, imposes its variegated expression state on the wild-typesulf ⁺ allele present insulf ⁺/sulf^vag heterozygotes. This behaviour, known as paramutation, has also been described for the originalsulf allele. The SC148 allele, however, seems to induce changes at an earlier stage in development. The analogy of this paramutagenic system to dominant position effect variegation inDrosophila is discussed.