云南产栎键蚧属一新种记述(同翅目:蚧总科,链蚧科)

寄生于壳斗科(Fagaceae)植物的蚧虫种类繁多,经初步整理,已达10科64属152种之多,几乎是我国已知蚧虫种类的1/5～1/4,其中栎链蚧属(AsterodiaspisSignoret,1876)是专性寄生类群之一。本属主要分布于东洋区,部分种类零星分布于全北区。本属迄今已知24种,其中我国已记载11种。我们在进行栎类蚧虫区系研究中,又发现该属1新种,现记述于下。异形栎链蚧Asterodiaspis deformis,新种(图Ⅰ,Ⅱ)     

链壶蚧属一新种：（同翅目：蚧总科：壶蚧科）

链壶蚧属Asterococcus隶属壶蚧科Cerococcidae,由Borchsenius 1960年建立。此属雌成虫以其外壳顶端有若虫蜕、外壳后部有一向上的管状突起物;8形腺在腹缘成明显的宽带及肛环刚毛8根,与本科中其它2属区别。链壶蚧属,目前世界已知7种,除1种分布在南非外,其余均分布在古北区和东洋区,我国目前已记载5种。本文记述了产于我国四川、湖南的链壶蚧属1新种。模式标本保存于山东农业大学昆虫学教研室昆虫标本室。 文中所涉及的长度单位均为微米(μm)。     

海南省链蚧科一新属一新种(半翅目:蚧总科)

记述链蚧科1新属——梭链蚧属Elagatis,并记述1新种:通什梭链蚧Elagatistongzaense,sp.nov.,模式标本保存于安徽工业大学。     

竹链蚧属一新种记述（同翅目：蚧总科，链蚧科）

本记述采自安徽歙县箸竹Indocalamus sp.上的链蚧属Bambusasis的一新种,凸腺竹链蚧Bambusasis prolrusus,sp.nov.     

中国新栎盾蚧属一新种及二新纪录种(同翅目:蚧总科:盾蚧科)

记述新栎盾蚧属Neoquernaspis Howell et Takagi,1981一新种,即细管新栎盾蚧N.leptosipha sp.nov和2种中国分布新纪录种,即石柯新栎盾蚧N.beshearae Liu et Tippins,1988和尼泊尔新栎盾蚧N.nepalensis (Takagi,1977),并编制了该属中国已知种类检索表,新种模式标本和新纪录标本保存于西北农业大学昆虫博物馆。     

云南紫胶蚧新种记述（同翅目：胶蚧科）

本文记述采自云南省寄生在钝叶黄檀枝条上的胶蚧属(Kerria)一新种,取名为云南紫胶虫(Kerria yunnanensis sp.nov.)。新种是云南紫胶原胶的大量生产者,分布较广泛,应用价值高,但因其外部形态与紫胶蚧(Kerria lacca(kerr)Targioni-Tozzetti)相似,长期以来一直被中外学者误认为是同一种。最近,经过对两者的形态作进一步观察比较,笔者认为是不同的种,新种与紫胶蚧是近缘种。新种的模式标本保存在中国林业科学研究院资源昆虫研究所。     

日仁蚧属一新种记述（同翅目：仁蚧科）

本文记述采自安徽省祁门县牯牛降自然保护区寄生于箭竹Sinarundinaria nitida(Mitf.)Nakai上的日仁蚧属Nipponaclerda一新种,箭竹日仁蚧Nipponaclerda triumpha,sp.nov.     

中国围盾蚧属一新种（半翅目：蚧总科：盾蚧科）

记述中国围盾蚧属Fiorinia Targioni-Tozzetti 1新种:南宁围盾蚧Fiorinia nanningensis Zhang&Feng sp.nov.。该种近似于钩樟围盾蚧F.linderaeTakagi,1969,二者臀板均无腺刺分布,并且第2臀叶退化,略突起或全无,但是可以从以下特征区别:1)新种中臀叶狭小,末端截型,内缘无锯齿(钩樟围盾蚧中臀叶大而内缘多齿);2)躯干上无腺刺或腺瘤(钩樟围盾蚧后胸有1-3个腺瘤,第1腹节有3或4个腺瘤,第2腹节有1-2个腺刺);3)无触角间突(钩樟围盾蚧触角间突小圆锥形)。对其形态特征进行了详细描述,提供了玻片绘图。研究标本保存在西北农林科技大学昆虫博物馆。     

我国发现一新入侵蜡蚧:三列鬃软蚧(半翅目,蚧总科,蜡蚧科)

本文记述采自中国惠州的1新记录属鬃软蚧属Trijuba De Lotto,该属目前只有1种,区别于蜡蚧科其他属的特征是雌成虫背面具有3列长刚毛。新记录种三列鬃软蚧Trijuba oculata(Brain)寄生于猴耳环Pithecellobium clypearia的枝干和叶柄上。     

中国蚁粉蚧属的初步研究（同翅目：蚧总科：粉蚧科）

记述我国蚁粉蚧属一新种：杨凌蚁粉蚧Formicococcus yanglingensis sp.nov.,建立一新组合;天麻蚁粉蚧F.gasteris(Wang,1982)comb.nov.(移自簇粉蚧属Paraputo Liang),并将F.gastrodiae Tang(1992)作为该种的异名处理。此外,还编制了蚁粉蚧属中国种类分种检索表。新种模式标本保存在南开大学生物系昆虫标本室。     

用离散量预测蛋白质的结构型

基于蛋白质的结构类型决定了它的二级结构序列的概念,用二级结构序列参数Nα,Nβ,Nβaβ,N(βαβ）构成离散源,并计算离散量D（Xα）,D（Xβ）,D（Xα＋β）,利用离散增量预测蛋白质的结构类型,它是由这个蛋白质的离散量D（Xn）与四个标准离散D（Xα）,D（Xβ）,D（Xα／β）,D（Xα＋β）之间离散增量的最小值所决定的,预测结果表明,准确率分别达到84．8％（标准集）和83．3％（检验集）。     

THE FIDELITY OF THE FOSSIL RECORD: THE IMPROBABILITY OF PRESERVATION

Abstract:  The fidelity of the fossil record reflects how accurately it preserves the history of life. Since Darwin's time any mismatch between our theories and the fossil record has been attributed to the imperfections of the record. For over a century scarcity of gradual evolutionary trends was explained in this way until the punctuated equilibrium model was proposed. A null hypothesis that all morphological patterns in the fossil record are unbiased random walks can be rejected because it predicts far more apparent trends than exist. Current best estimates suggest that trends occur in at most 5% of characters. When an organism dies either it becomes fossilized or it doesn't. To be confident a species has not been preserved the probability against preservation must be significantly larger than the total number of individuals of that species that ever existed. For skeletized species preservation was the norm not the exception. Nevertheless, fossils must then avoid subsequent destruction and be discovered to be useful.     

THE ONTOGENY OF CARBONIFEROUS ARTICULATES: THE APEX OF SPHENOPHYLLUM

Twig apices of Sphenophyllum lescurianum, S. constrictum, and two new Sphenophyllum taxa are described in transverse and longitudinal section from middle and upper Pennsylvanian age specimens. In all of the species the single apical cell has the shape of a tetrahedron, with a triangular upper surface and three internal cutting faces. Segment cells are produced from each of the cutting surfaces in a dextrorse or sinistrorse direction, depending upon the species. The central portion of each segment cell contributes to the initiation of the procambium, while the remaining outer portion undergoes a vertical and subsequent horizontal division to form segment cells. Segment cells are aligned in vertical tiers beneath the respective apical cell cutting faces, with the individual leaves positioned directly beneath a tier of segment cells. Leaf primordia are first observed as a series of surface undulations below the apex, with an intercalary meristem located directly beneath each primordium. The vegetative apical organization of Sphenophyllum is demonstrated to be very similar to the type of organization found at the stem tips of Catamites and Equisetum.