三疣梭子蟹胚胎发育过程中卵内幼体形态

三疣梭子蟹胚台发育过程中,卵内幼体共经历2期卵内无节幼体和3期卵内tao状幼体,各幼体期的主要特征表现为：第1期卵内无节幼体具小触角,大触角和大颚3对附肢,第2期卵内无节幼体除草1期的3对附肢外,2对小颚开始出现,腹部前端分节,第1期卵内tao状幼体阶段复眼先为棒状,继而变成月牙状,附肢5对,腹部分为6节,第2期卵内tao状幼体阶段2对颚足出现,复眼发育完全,卵黄蝶状,心脏开始跳动,到此阶段末期,附肢分节和分叉,第3期卵内tao状幼体阶段,各器官进一步发育,肌肉明显。     

东方鱼虱的生活史

1.从非洲鲫鱼的鱼体上和对成熟卵囊的短期培养,获得了东方鱼虱的幼虫和成虫的各期标本,共发现无节幼体二期,桡足幼体一期,附着幼体五期,以后即为成虫期。 2.第一无节幼体有三对附肢和一对尾叉,三对附肢除第一对为单肢型外,其余均为双肢型。后期无节幼体身体增长,体内已孕育着下一期幼体的分节和一些附肢。 3.桡足幼体这期出现了变态,身体分节,可分头胸、胸、腹三部分,呈剑水蚤型。头胸部有下列几对附肢:第一触角、第二触角、大颚、第一小颚、第二小颚、第一颚足、第二颚足和第一对游泳足。胸部有三个自由胸节,前二节各着生一对附肢,即第二、三对游泳足。第一、二对游泳足为双肢型,第三对游泳足为一突起具1长1短二根刚毛。额丝盘曲在头胸部腹面前部。腹部一节,尾叉一对,尾刚毛5根。 4.附着幼体期,是虫体放出额丝营吸附生活的时期。头胸甲逐渐扩大,胸部的第一自由胸节,逐渐与头胸甲愈合,第二自由胸节逐渐缩小,第三自由胸节逐渐膨大成为生殖节。第四期附着幼体,即出现了雌雄性的区别。雄性的生殖器官要比雌性的成熟得早,第五期 附着幼体,雄性已成熟,而雌性尚未完全成熟,交配是在第五期附着幼体蜕皮后,这时的雌雄性,均可营寄生生活或作短期自由游泳。雌雄两性的主要区别,在第二触角、第二小颚、第二颚足、生     

云南省库蠓一新种(双翅目:蠓科)

1965年采自云南省蒙自县的蠓类标本中,发现一新种库蠓,记述于下。角突库蠓Culicoides corniculus,新种 雌蠓 头部:两复眼光裸、分离,复眼间距约为1—1.5个小眼面直径的宽度,复眼间有上横缝。触角第Ⅲ、Ⅺ—ⅩⅠⅤ节具有感器,触角比约1.2。下颚须第3节端半部有一浅感窝。上颚齿约15个,外颚叶齿约16个,口甲上无小棘刺。     

我国常见的海产多毛环节动物

我国常见的海产多毛环节动物孙瑞平,杨德渐（中国科学院海洋研究所青岛）（青岛海洋大学生物系２６６００３）多毛环节动物是环节动物中以海洋物种为主的最大的一个纲。身体由头部、躯干部和尾（肛）部组成。头部的口前叶和围口节常具感觉附肢（触角、触手或触须）或具外...     

误食马陆(千脚虫)致口唇过敏性水肿1例报告

马陆[Prospirobtus joahnsi(Brolenann)]为圆马陆科动物约安臣马陆或其它马陆类动物的全虫。别名：刀环虫、百节虫、千脚虫、蓖子虫、锅耳朵、大草鞋虫、百脚陆。体长圆形,表面光滑。长约12cm,宽约7mm,虫体由多个环节组成,从颈板到肛节,约有54个体节。头部两侧有许多单眼,集合成2团,形似复眼。触角1对,有毛,长约5mm。口器包括大小颚各1对,小颚愈合成为颚唇。体背面黑褐色,前缘盖住部分淡黄色。颈板半圆形,深褐包。第2～4节为胸部,每节各有步肢1对。第5节以下为腹部,除末节外,每节有步肢2对。雄虫在第7节上的步肢变为生殖器。自第6背板后各体节的两侧,有臭腺孔。幼虫环节少,仅有3对足,每蜕皮1次,则体节和足陆续增加。马陆多栖于阴湿地区,食草根及腐败的植物,触之蜷缩不动,并放出恶臭。全国大部分地区均有分布。现报告1例幼儿误食马陆致口唇过敏性水肿的治疗情况。     

昆明果蝇属一新种：双翅目：果蝇科

长鬃果蝇Drosophila(Drosophila)Iongisetae sp.nov.新种(图A—F) 体长:4.5mm,翅长4.0mm. 头部:复眼红色,具稀疏的微毛。触角第2节黄色,具2小刚毛,第3节棕黄色,触角芒上侧具3个分枝毛,下侧具1个分枝毛,末端分叉大、下颚须黄色,具2根鬃。额黄     

蜈蚣和马陆

节肢动物门(Arthropoda)中的唇足纲(chilopoda,俗称蜈蚣)和倍足纲(Diplopoda,俗称马陆),与烛(虫戋)类(Pauropoda)(图1-A,B)、综合类(Symphyla)(图1-C)一起,通称为多足动物(Myriapoda)。多足动物,陆生,以气管呼吸。体形呈蠕虫状,身体由许多体节及其分节的步足组成,全体一般分为头部和躯干部。头部的触角只有1对,口器由1对大颚和1或2对小颚组成。大颚不具有触须(palps)。雌雄异体。有几丁质化的外骨骼,常因含有钙质可与十足类(如毛蟹等)的甲壳强度相比拟。随着个体生长发育的各个时期,而要有规律地蜕皮。蜈蚣和马陆是两类最常见的多足动物。     

中国平背叶蜂族一新属新种(膜翅目,叶蜂科,平背叶蜂亚科)

记述了中国膜翅目叶蜂科平背叶蜂亚科平背叶蜂族1新属新种:红环申氏叶蜂Shenia rufocincta Wei et Nie,sp.nov.新属Shenia Wei与Apethymorpha Wei(1997)稍有些类似,但唇基和唇基上区十分平坦,唇基缺口较浅,上唇小,颚眼距明显宽于单眼直径,触角窝上突显著发育,触角第2节窄长,后翅Rs室封闭,后足跗节显著长于胫节,基跗节显著短于其后4节之和等,与后者差别较大.本属唇基平坦,缺口很浅,上唇甚小,颚眼距很宽,触角第2节长大,触角窝上突显著发育,前翅具4肘室,cu-a脉基位,后翅臀室具长柄,Rs和M室均封闭,R1室无附室等,可以与平背叶蜂族各属相鉴别.该种模式标本采自河南省嵩县白云山.模式标本保存于中南林学院昆虫标本室.     

荒川库蠓雌雄成虫形态和超微结构

【目的】为了更加准确地进行蠓科(Ceratopogonidae)昆虫的分类鉴定,获得更全面、细致的荒川库蠓Culicoides arakawai(Arakawa)雌雄成虫形态和超微结构特征。【方法】利用扫描电子显微镜对荒川库蠓雌雄成虫形态和超微结构特征进行观察研究。【结果】获得荒川库蠓雌雄成虫复眼、触角、口器、翅、盾板、足和生殖器等性状特征扫描电镜图共计31幅,其中包括精确的体躯量度值,如雌虫触角鞭节各节长度比值为4.80∶3.22∶3.56∶3.54∶3.44∶3.56∶3.56∶3.86∶7.32∶6.96∶7.02∶7.40∶9.78,雌虫触须各节长度比值为2.90∶7.47∶8.07∶2.58∶3.92;雌雄虫翅大小分别为1.34~1.36 mm×0.56~0.66 mm和1.22~1.32 mm×0.40~0.48 mm;受精囊大小为71.87μm×48.07μm。观察到已知特征未被描述的细节,如雌虫小颚齿19枚,分两排排列,雄虫小颚具12~13枚细长小颚齿;雌虫小盾片梯形,具4根粗鬃和6~8根细鬃;雌虫后足距的表面具排列成扇状细毛;雌虫爪端部分叉,爪间突具4对毛状分支;雌虫受精囊表面具刻点,基孔与受精囊宽度比值约为1/9;雄虫尾叶内表面具微毛和大毛及特殊结构。发现新特征——爪毛。通过对比发现荒川库蠓性二型现象明显,如雌雄成虫在触角形态、触角感器的类型及其分布、大颚和小颚的形态及齿的数量和形状、舌的形态及翅形等性状特点上均存在明显差异。【结论】本研究为荒川库蠓的准确鉴定及蠓科昆虫分类学和系统学研究提供参考依据,并具有重要的经济学及医学意义。     

云南松叶蜂科七新种 (膜翅目:广腰亚目)

本文记述了中国云南省松叶蜂科Diprionidae七个新种。所有模式标本均保存于中国林业科学研究院林业科学研究所森林昆虫标本室。1.永仁吉松叶蜂 Gilpinia yongrenica Xiao et Huang,新种 雌虫:体长6.7毫米。黑色,具光泽及淡色斑纹;触角黑色,1、2节及3节基部带黄褐色。头部上颚大部分红褐色;须、上唇、唇基、唇基上区,触角侧区、颚眼距、颊、眼上区,单眼后区两侧均黄白色。胸部前胸背板两侧角、中胸前盾片两侧及后端、中胸     

A simple and inexpensive system for monitoring jaw movements in ambulatory humans

A simple and inexpensive method for recording vertical movements of the human mandible relative to the maxilla is presented. Measurements are made from accelerometers and a Hall-effect device temporarily glued to the upper and lower anterior teeth. The accelerometer signals are integrated once to give velocity and a second time to give position. Movements of the mandible relative to the maxilla are obtained by integrating the difference between the two accelerometer signals. The (relative) velocity and position records derived in this way are linear, but subject to drift when the jaw is stationary. Steady mandibular position is obtained from the Hall-effect system, but this signal must be corrected for its inherent non-linearity. This device can record rapid movements of the mandible even when the head is unrestrained, and interferes minimally with normal jaw movements.     

Feeding mechanics in primitive teleosts and in the halecomorph fish Amia calva

The mechanics of feeding in Salmo gairdneri and Hoplias malabaricus, two generalized predaceous teleosts, was studied using high-speed movies (200 frames per second). In Hoplias, the feeding mechanism is characterized by an extreme anterior swing of the maxilla and rapid depression of the hyoid occurring synchronously with mandibular depression and neurocranial elevation. A similar feeding sequence is observed in Salmo although the movements of the head are neither as extreme nor as rapid.
The anterior swing of the maxilla, usually attributed to mandibular depression, increased when the ligamentous connection of the maxilla to the mandible was severed. A mechanical model of the jaw was constructed to elucidate the functional interrelationships of the neurocranium, maxilla and mandible.
Films of the "holostean" Amia calva feeding show that the feeding mechanism is of a fundamentally different nature than that of primitive teleost fishes. Extreme anterior swinging of the maxilla occurs synchronously with jaw opening but branchiostegal expansion and hyoid depression only reach a maximum well after the jaws have begun to close. The existence of a highly efficient levator operculi—opercular series—mandible coupling is hypothesized on the basis of the rapid initial jaw opening.
This pattern of feeding movements in Amia has necessitated a revision of current theories on the nature and significance of the "holostean"     

Postural stability of the human mandible during locomotion

Movements of the head and of the mandible relative to the head were measured in human subjects walking and running on a treadmill at various speeds and inclinations. A miniature magnet and piezo-electric accelerometer assembly was mounted on the mandibular incisors, and a Hall-effect sensor along with a second accelerometer mounted on a maxillary incisor along a common vertical axis. Signals from these sensors provided continuous records of vertical head and mandible acceleration, and relative jaw position. Landing on the heel or on the toe in different forms of locomotion was followed by rapid deceleration of the downward movement of the head and slightly less rapid deceleration of the downward movement of the mandible, i.e., the mandible moved downwards relative to the maxilla, then upwards again to near its normal posture within 200 ms. No tooth contact occurred in any forms of gait at any inclination. The movement of the mandible relative to the maxilla depended on the nature and velocity of the locomotion and their effects on head deceleration. The least deceleration and hence mandibular displacement occurred during toe-landing, for example, during "uphill" running. The maximum displacement of the mandible relative to the head was less than 1mm, even at the fastest running speed. The mechanisms that limit the vertical movements of the jaw within such a narrow range are not known, but are likely to include passive soft-tissue visco-elasticity and stretch reflexes in the jaw-closing muscles.     

梨小食心虫幼虫感受器扫描电镜观察

梨小食心虫Grapholita molesta(Busck)是一种世界性蛀果害虫,主要以幼虫钻蛀蔷薇科果树的嫩梢和果实进行为害.本文利用扫描电子显微镜观察了梨小食心虫幼虫的超微形态和感受器.结果表明,幼虫触角上有3种类型的感受器:2个刺形感受器、6个锥形感受器和1个栓锥形感受器.上唇有6对刺形感受器.上颚的前端有切齿叶.在下颚的轴节和茎节各有1个刺形感受器.每个外颚叶有3个短而尖的锥形感受器、2个大的栓锥形感受器和3个刺形感受器.体节末梢的下颚须有7个锥形感受器、1个栓锥形感受器.下颚须的末端有1个指形感受器和2个板形感受器.每个下唇须末端具有1个尖锥状刺形感受器和1个长的栓锥形感受器.胸足与腹足上也分布有不规则的毛型感受器和刺型感受器.该研究将为进一步阐明梨小食心虫与其寄主的关系提供形态学的理论基础.     

New approach to the gummy smile

The authors present a multidisciplinary approach to the gingival smile in which its three components are evaluated. These components are the dynamic component of the lip (repose versus smiling) and the two static elements of the gum and maxilla. Once an appropriate diagnosis has been made, the authors act on the gingiva for delayed passive eruption, on the maxilla for long face syndrome, and on the lip with lip-elongation techniques. When delayed passive eruption is associated with hyperfunction of the lip elevators, an intraoral approach with an incision at the level of the upper labial frenulum and dissection from the anterior nasal spine to the anterior maxillary fossae, in addition to gingival remodeling, is recommended to reduce gingival exposure.     

A new species of Platydracus Thomson, 1858 (Coleoptera,Staphylinidae, Staphylininae) from the upper Eocene Florissant beds,Colorado, USA

Platydracus breviantennatus n. sp., is described and figured based on an impression fossil from the upper Eocene Florissant beds of Colorado, the United States. Based on the large and densely setose body, relatively small eyes, and robust mandibles (right mandible seemingly with one simple preapical tooth), tibiae and antennae, the new species is placed in the modern genus Platydracus Thomson, 1858. It differs from other species of Platydracus by its large body, small head, and distinctly short antennae.     

Orthodontic status and head morphology in young males

Complete anthropometrical data on a sample of 111 Russian males aged 20.0+/-2.3 years were obtained to investigate craniofacial morphology according to individual orthodontic status (OS). Subsample analyses were performed, using a variety of grouping factors. a) 1-spacing on both dental arches; 2-absence of crowding, spacing, rotation, or displacement of teeth on both dental arches; 3-crowding on both dental arches; b) 1-spacing on mandible; 2-absence of crowding, spacing, rotation, or displacement of teeth on mandible; 3-crowding on mandible; c) 1-spacing on maxilla; 2-absence of crowding, spacing, rotation, or displacement of teeth on maxilla; 3-crowding on maxilla. Wilks' Lambdas were found to be 0.29 to 0.59; all were significant. CONCLUSIONS: 1. Significant positive and negative correlations were found between craniofacial measurements and an individual's OS. 2. Measurements exhibited statistically significant differences between the groups with different OS at the p<0.05 level and some at p<0.01. 3. Using forward stepwise discriminant analysis, a high difference in craniofacial architecture between the groups with different OS was found. Canonical discriminant analysis indicates the face pattern connected to crowding: relatively high medial vertical mandible height in combination with a vertically long and narrow face; to spacing: a wide face with wide nose and high upper lip is combined with shortened medial vertical mandible height. 4. Depending upon the grouping factor, 10 to 12 variables were chosen in the canonical discriminant model. Classification functions and means of canonical roots were calculated; morphological interpretations of canonical roots were performed. 5. Definitive OS is a complicated product of interaction during the ontogenesis of jaws between the time of teeth eruption and the growth of two growth fields (alveolar and corpus) under the simultaneous influence of hormonal status and the chronological age of the individual.     

A comparison of the craniofacial morphology in 2-month-old unoperated infants with unilateral complete cleft lip and palate, and unilateral incomplete cleft lip.

This paper reports a cephalometric analysis of the craniofacial morphology in infants with unoperated unilateral complete cleft lip and palate (UCCLP) and unoperated unilateral incomplete cleft lip (UICL). The purpose of the study was to determine the nature and extent of the craniofacial deviations in UCCLP as compared to the morphology in UICL, which has previously been shown to be close to normal. The samples comprised 82 infants with UCCLP (58 males and 24 females) and 75 with UICL (48 males and 27 females). The mean age was about 2 months in both groups. The cephalometric analysis of craniofacial morphology included the lateral, frontal, and axial projections. The data were presented as mean plots of the craniofacial region including the calvaria, cranial base, orbits, nasal bone, maxilla, mandible, cervical column, pharynx, and soft-tissue profile. The most pronounced deviations in the UCCLP group were observed in the maxillary complex and the mandible. The most striking findings were: markedly increased width of the maxilla, a short mandible, and bimaxillary retrognathia except for the premaxillary area, which was relatively protruding and asymmetric. The study did not support the hypothesis previously suggested in the literature that cleft lip and palate is a craniofacial anomaly as size and shape of the calvaria and cranial base were found to be normal. The etiology of cleft lip and palate is still incompletely understood. Based on the present study, we suggest that facial type may be a liability factor that could represent a developmental threshold increasing the probability of cleft lip and palate.     

Duplication of stomatodeal structures: report of three cases with literature review and suggestion for classification

Three cases of duplications of stomatodeal structures are reported. One had an accessory mouth that could move simultaneously with his mouth at sternal notch. Another had a teeth-bearing bony mass at left maxilla with excessive upper lip and a false pouch. The third had an excessive upper lip, upper jaw with teeth, and hard and soft palate. The literature is reviewed, and a classification is suggested: type I, a duplicated mouth; type II, duplication of maxilla-upper lip or mandible-lower lip complex; and type III, centrally located, poorly developed lip-jaw duplication.