ENDOCYTOSIS IN THE CROP OF THE SLUG, DEROCERAS RETICULATUM (MULLER) AND THE EFFECTS OF THE INGESTED MOLLUSCICIDES, METALDEHYDE AND METHIOCARB

Utilising the markers horseradish peroxidase (HRP) and lanthanumnitrate, uptake of endogenous material was demonstrated in thecrop of the slug, Deroceras reticulatum. Pinocytosis of HRPwas observed to occur rapidly, (within 5 min post feeding) inspecimens that had previously been starved for 48 h. Similarrates of uptake were recorded for lanthanum but this markerwas confined to a paracellular route. The effects of the molluscicidesmetaldehyde and methiocarb, following ingestion were studiedat the electron microscope level. At sub-lethal doses morphologicaldamage to the surface epithelium of the crop was attributableto both active ingredients. In addition the appearance of intracellularvacuoles within crop cells was evident from 24 h post treatmentwith methiocarb. (Received 7 February 1990; accepted 4 April 1990)     

AGENCY, PERSONHOOD AND THE 'I' OF DISCOURSE IN THE PACIFIC AND BEYOND

Sahlins bases his account of Polynesian 'heroic history' partly on the fact that chiefs used the pronoun 'I' in reference to their whole group. Mosko (1992) argues that Sahlins's consequent emphasis on 'encompassment' as the modality of chiefly action is diametrically opposed to Strathern's on 'partibility', the effacement of parts of the person as a condition of action. Drawing on comparative material from the New Guinea Highlands, where big men also use 'I' for their whole group, and on Benveniste's and Urban's accounts of the meaning and use of personal pronouns, I argue instead that moments of both encompassment and partibility are inherent in language, corresponding to two distinct dimensions in which the pronouns are meaningful (the 'direct indexical' and the 'anaphoric'), and that close attention to the interaction between the two can yield new insights into the nature of personhood and social agency.     

新疆准噶尔盆地早中新世的最早众古仓鼠及其与稀古仓鼠的对比(英文)

记述了新疆准噶尔盆地早中新世地层中发现的众古仓鼠类化石。材料采集于索索泉组的两个地点,古地磁年龄介于21.9～21.16Ma之间。这是迄今为止中亚和东亚地区众古仓鼠的最早记录。材料可以归入两个种:苏氏众古仓鼠(新种)Democricetodon sui sp.nov.和众古仓鼠未定种Democricetodon?sp.,该未定种材料很少,不足以准确分类。与早中新世其他仓鼠的比较及对稀古仓鼠Spanocricetodon模式种的重新观察表明,苏氏众古仓鼠是中亚地区谢家期的指示性化石,李传夔(1977)所定义的稀古仓鼠为一个有效属,与Democricetodon和Primus属有明显区别;以前归入稀古仓鼠的某些种类应归入其他属。苏氏众古仓鼠与同一地区晚渐新世的Eucricetodon aff.E.caducus形态明显不同,表明它可能不是起源于该地区的古近纪仓鼠,而是迁移至中亚的外来种。     

THE ROLE OF THE ENDOSPERM IN THE GERMINATION OF LEGUMES: GALACTOMANNAN,NITROGEN, AND PHOSPHORUS CHANGES IN THE GERMINATION OF GUAR (CYAMOPSIS TETRAGONOLOBA; LEGUMINOSAE)

The endosperm of Cyamopsis tetragonoloba (“guar”) contains 41 % of the dry weight and 45 % of the acetone-insoluble-solids of the seed, but only 3–11 % of the nitrogen and phosphorus. At least 75 % of the acetone-insoluble-solids of the endosperm is galactomannan, only about 12% being accounted for as pentosan, pectin, protein, phytin, ash, and dilute-acid-insoluble residue. During a five-day germination period at 30 C, all of the galactomannan and all but 5 % of the dry weight of the endosperm disappeared, being translocated to the cotyledons. About ⅓ of the nitrogen and phosphorus of the endosperm plus seed coat were also translocated. After a 36-hr lag, the accumulation of the nitrogen and acetone-insoluble-solids in the seedling axis were linear, while the total dry weight and phosphorus showed a rapid increase followed by a slower accumulation during the five-day period. In the cotyledons, the dry weight temporarily increased, but the acetone-insoluble-solids, nitrogen and phosphorus showed only a net decrease after 84, 36 and 36 hr, respectively. Scanning election micrographs of dry-fractured and sectioned endosperm show that the bulk of the endosperm is a solid mass of galactomannan with essentially no cell lumina; a several-cell layer (“aleurone”) of thick-walled cells of similar structure is metabolically active.     

THE PHOTOSYNTHETIC EFFICIENCY OF PHYCOCYANIN IN CHROOCOCCUS,AND THE PROBLEM OF CAROTENOID PARTICIPATION IN PHOTOSYNTHESIS

The absorption spectra of the principal pigment components extracted from Chroococcus cells have been measured, and their sum compared with the absorption of a suspension of living cells. The agreement was sufficiently close so that it was concluded the absorption spectra of the extracted and separated pigment components could be used to obtain estimates of the relative absorption of the various components in the living cells. The quantum yield of Chroococcus photosynthesis was measured at a succession of wave lengths throughout the visible spectrum, and the dependence of yield on wave length was compared with the proportions of light absorbed by the pigment components. This comparison showed beyond reasonable doubt that the light absorbed by phycocyanin is utilized in photosynthesis with an efficiency approximately equal to that of the light absorbed by chlorophyll. The light absorbed by the carotenoid pigments of Chroococcus seems for the most part to be unavailable for photosynthesis. The results leave open the possibility that light absorbed by the carotenoids is active in photosynthesis, but with an efficiency considerably lower than that of chlorophyll and phycocyanin. It is also possible that the light absorbed by one or a few of the several carotenoid components is utilized with a high efficiency, while the light absorbed by most of the components is lost for photosynthesis.     

大头茶族的范围及族内属的界限

广义大头茶族几乎包括了整个山茶亚科的属,分群的界限不够明确,易于造成混乱,经过研究,作者所持的是狭义大头茶族的概念。考察这一族包括Polyspora, Gordonia和Laplacea三个属形态特征上的差异和洲际分布的事实,这三个属虽然有共同的祖先,但由于演化上的歧异,仍应作为独立的属看待。在划分属的界限上,苞被分化与否和花部其他形态的差异具有最重要的意义,花粉表面纹饰的差异也可作为一种依据。Polyspora种群划分也被讨论。     

VASCULAR SUPPLY AND STRUCTURE OF THE OVULE AND ARIL IN PEONY AND OF THE ARIL IN NUTMEG

Camp , Wendell H., and Mary M. Hubbard . (U. Connecticut, Storrs.) Vascular supply and structure of the ovule and aril in peony and of the aril in nutmeg. Amer. Jour. Bot. 50(2): 174–178. Illus. 1963.—Examination of the placental region in the carpel of Paeonia indicates a complexity and super-abundance of vascular supply beyond that usually found in angiosperms and certainly more than is necessary for adequate nutrition and water supply of the ovules. From this it is concluded that the ovules once were borne on a larger and more complex structure than the present carpel. Vascular strands leading to the aril and the hypostase are interpreted as being relictual. The large multifid aril of Myristica has a well-developed vascular system composed of several sizes of branched bundles.     

危害竹子的飞虱类昆虫区系及生物地理学初探(半翅目,蜡蝉总科,飞虱科)

对世界取食、危害竹子的飞虱类昆虫的物种多样性、区系成分和分布特点进行了统计、分析,并对该类昆虫的分布格局及可能的起源与演化路径进行了初步研究。结果表明:截至目前全世界共记录竹子飞虱20属105种,均隶属于飞虱亚科,以凹距飞虱族为优势类群,有18属95种,分别占竹子飞虱属、种数的90%和90.5%,余下的为飞虱族的类群;竹子飞虱主要分布于东洋界(16属96种,占91.4%)和新热带界(6属13种,占12.4%),少数属种可渗透分布至古北界;竹子飞虱的特有属、种极为丰富,特有属13个,占竹子飞虱总属数的65%,特有种89个,比例高达84.8%;竹子飞虱可能起源于新生代第三纪的冈瓦纳古陆,东洋界的中国南部和南亚诸岛是竹子飞虱的现代分布和分化中心,新热带界的厄瓜多尔可能是竹子飞虱的又一现代分布和分化中心。     

晋冀鲁豫接壤区生态灾害及灾情评估研究

晋冀鲁豫接壤区的发展在我国经济发展战略中起着承东启西的重要作用。而制约该区经济发展和主要因素之一则是生态灾害,通过对自然灾害类型的划分及其成因的分析,进行灾情评估与排序,找出不同地区所受影响较大的灾种,以及所受不同灾害的轻重程度,以便为发展经济制定对策,使该区在生态上得以改善,经济上得以发展。     

我国更新世两属鬣狗(Hyaena,Crocuta)的关系与分类

多数学者认为,更新世的两属鬣狗与现生两属鬣狗相比,化石Hyaena不同于现生Hya-ena,而与Crocuta更为相近。本文结合近年来采集的新材料的研究,进一步论证了化石Hya-ena与Crocuta的密切关系,并且赞成把我国的Hyaena licenti和H.sinensis的属名订正为Pachycrocuta。     

THE STRUCTURE OF THE FEATHERS IN CHLOROPHANES AND IRIDOPHANES (COEREBIDAE).

Structurally coloured feathers from the Coerebid Chlorophanes show atypical features. These may be connected with different conditions of compressibility during development, as compared with typical feathers and mammalian fibres; there, cortex is more compressible than medulla.
The atypical cortex has a special function in connection with the structural shade. The conditions in Iridophanes are similar to those in Chlorophanes , but less marked. Close relationship between these two genera, as suggested by earlier authors, is therefore confirmed.