蕨类植物桂皮紫萁颈卵器和精子器形态和发育的研究

利用扫描电镜技术和树脂切片技术对蕨类植物桂皮紫萁（Osmunda cinnamomeaL.var.asiatica Fernald)的颈卵器和精子器的形态和发育进行了细致的研究。颈卵器发生于雌配子体的腹面,颈部由4列壁细胞构成,6-7个细胞高,内部含有颈沟细胞,腹沟细胞和卵细胞,卵细胞在整个发育过程中,造粉体和囊泡最为显著,颈卵器内的卵细胞成熟时产生卵膜和分离腔。精子器发生于雄配子体的边缘及腹面,由7-8个壁细胞螺旋状围绕而成,壁细胞内为产精组织,精子成熟时精子器盖细胞开裂释放出游动精子。     

NUTRITION OF CHYTRIOMYCES AND ITS INFLUENCE ON MORPHOLOGY

The nutrition and its influence on some morphological characteristics of one isolate of Chytriomyces aureus Karling and two isolates of C. hyalinus Karling, one with and one without resting bodies, was studied. All three isolates required exogenous thiamine for optimum growth. Glucose, fructose, mannose, maltose, cellobiose, and starch supported good or moderate amounts of growth of all the isolates. Galactose, arabinose, xylose, ribose, sucrose, lactose, and raffinose supported little or only trace amounts of growth of C. hyalinus, with resting bodies, but failed to produce any growth of C. aureus and C. hyalinus, without resting bodies. All isolates utilized ammonium [NH₄NO₃, (NH₄)₂SO₄, NH₄Cl] as nitrogen sources but were unable to utilize nitrate (KNO₃) and nitrite (KNO₂). All isolates were able to grow at pH ranges of 5–8; the optimum pH range was 6.5. Both isolates of C. hyalinus were able to grow at a temperature of 10–30 C, whereas C. aureus did not grow below 15 C or above 25 C. Sporangial size was influenced by varying temperature levels, pH ranges, vitamins, carbohydrates, and nitrogen sources, while the morphology and sizes of zoospores, lipoid globules, apophyses, and rhizoids were little affected. The similarity of response exhibited by both species of Chytriomyces to various nutrients may suggest that these are closely related taxa.     

THE INFLUENCE OF SEA ANEMONES ON THE MORPHOLOGY AND PRODUCTIVITY OF TWO INTERTIDAL SEAWEEDS1

The intertidal seaweeds Corallina vancouveriensis Yendo and Gelidium coulteri Harv. respond to the experimental removal of associated mats of the clonal anemone Anthopleura elegantissima Brandt with morphological changes that affect their photosynthetic performances. With the removal of anemones, these seaweeds develop a tight compaction of thalli which aids in the retention of moisture during aerial exposure. The morphological response, however, results in greatly reduced net photosynthesis in C. vancouveriensis (–98%) and G. coulteri (–73%) on an areal basis. Association with the clonal anemones allows these seaweeds to maintain a morphology that is more highly productive yet inconsistent with the exposure stresses in many microhabitats at similar tidal levels.     

非洲和中国直立人某些颅骨特征的比较--中国与非洲人类头骨特征对比之一

针对学术界有关非洲与亚洲直立人关系的争论,本文对一些用来支持非洲早期直立人从直立人中分离出来而归入匠人的主要形态学证据进行了检验,用于研究的标本包括迄今在东非发现的年代最早的直立人KNM－ER 3733、KNM－ER 3883和KNM－WT15000头骨化石,这些石是被提倡非洲与亚洲的直立人分离两个种的学者归入匠人的主要标本,对这些非注早期直立人与中国直立人18项头骨特征对比显示：一些被认为是局限于亚洲直立人的独有特征在上述非洲直立人头骨都有出现,存在于非洲直立人与中国直立人之间的颅骨特征上的差别主要体现在特征的表现程度与方式的不同,作者认为根据本文对比的颅骨特征,非洲直立人与中国直立人在颅骨形态上非常相似,他们之间的形态差异反映了直立人具有较宽的形态变范围,认为亚洲直立人具有特化的衍生性状的观点在本文不能得到支持。     

鲤形目鱼类咽齿形态及发育的比较研究

对鲤形目所属６科类的咽龄形态及个体发育模型进行了较详细的比较研究。结果得出除双孔鱼科鱼类未形成咽齿外,其它５科鱼类在咽齿发生的过程中具有齿着生方向完全相反的两种发育模式。以亚口鱼科,鳅科和平鳍鳅为一类的齿后向增长的类型和以鲤科另一类的齿同增长的类型。     

MORPHOLOGICAL AND HISTOLOGICAL EFFECTS OF TRIFLURALIN ON ROOT DEVELOPMENT

The most obvious external effect of trifluralin on the primary root was an increase in the amount of radial expansion near the root tip. The initial radial expansion of the treated roots occurred in the region of maximum elongation. With increased duration of treatment there was a gradual decrease in the extent of the meristematic tissue zone because of progressive vacuolation and subsequent differentiation. Although trifluralin disrupted the mitotic process, no one type of mitotic figure prevailed. Mitotic activity was not affected in all of the cells, some of which appeared to be undergoing a perfectly normal mitosis. Rates of trifluralin application sufficient to inhibit lateral root emergence without interfering with development of the primary root affected the pericycle and portions of the endodermis. The pericyclic cells were much enlarged in. the regions opposite the protoxylem and had undergone some of the initial phases of lateral root formation. These enlarged pericyclic cells correspond to what have been called primordiomorphs.     

体色异常褐牙鲆皮肤色素及鳞片发育的形态学研究

本文观察比较了体色正常及体色异常褐牙鲆 (Paralichthysolivaceus)皮肤中黑色素胞和鳞片的发生及演变过程。结果显示仔鱼鱼体两侧皮肤中最先出现星状幼体型黑色素胞 ,随着变态发育 ,有眼侧皮肤中成体型黑色素胞逐渐替代幼体型黑色素胞 ;而无眼侧皮肤中 ,幼体型黑色素胞逐渐退化崩解 ,成体型黑色素胞不出现 ,无眼侧皮肤逐渐失去色素变为白色。体色异常现象出现于变态后期 ,白化和黑化现象几乎同时发生。白化个体有眼侧皮肤中成体型黑色素胞不能正常替代幼体型黑色素胞 ,逐渐失去色素形成白色斑块。黑化个体无眼侧皮肤中成体型黑色素胞则非正常地出现 ,逐渐替代幼体黑色素胞形成黑斑。约 30日龄变态完成时 ,体色异常现象已经显著 ,已能明显区分体色正常和异常个体。 6 0日龄左右 ,幼鱼皮肤开始长出形态较为原始的圆鳞。体色正常个体有眼侧皮肤上的圆鳞会逐渐发育成栉鳞 ,无眼侧则维持圆鳞。对比分析体色异常个体的鳞片形态 ,发现有眼侧白化部位的鳞片仍为圆鳞 ,而无眼侧黑化部位的鳞片则发育为栉鳞。同时 ,通过对体色正在恢复中的白化牙鲆的鳞片观察表明 ,伴随着白化部位色素的恢复 ,该部位的圆鳞会逐渐转变为栉鳞。由此推断色素的发生与鳞片的发育密切相关     

BIOACOUSTICS OF DOMESTICATION: ALARM AND COURTSHIP CALLS OF WILD AND DOMESTIC CAVIES

ABSTRACT

Comparisons of wild (Cavia aperea) and domestic (C. porcellus) cavies promote an understanding of the physiological and behavioral effects of domestication. The richness and peculiarities of Cavia acoustic repertoires encourage the use of this model for testing how domestication alters repertoires and the physical structure of calls. We present a comparison between alarm and courtship calls of domestic and two populations of wild cavies from different geographic regions, one of them with a short-term captivity history of 25 generations. We found significant differences between domestic and wild cavies in both calls, particularly in temporal parameters, and only spectral differences between two wild populations in alarm calls. There were also differences in the frequency of emission of calls: alarm calls were more frequent in the wild and courtship calls were more frequent in the domestic species. Our results suggest that domestication has influenced the temporal parameters of both alarm and courtship calls of C. porcellus, but not the spectral parameters that, instead, may be influenced by environment or population factors.     

THE INFLUENCE OF ENVIRONMENTAL LIGHTING ON THE GROWTH AND PROMETAMORPHIC DEVELOPMENT OF LARVAL RANA PIPIENS

This study was designed to investigate whether the larval development of an anuran amphibian could be modified by raising the animals in continuous light or darkness instead of under conditions of diurnal illumination, and to quantify the effects of these treatments at various intervals during this period of development.
Larvae of the frog, Rana pipiens , were raised through metamorphosis under conditions of constant light, constant darkness, or diurnal lighting. As measured by stages of development, body weight, tail length and body length at 20-day intervals, no significant differences in growth rate or metamorphic change were observed until near the middle of the prometamorphic period, which began at approximately the 50th day of development. After midmetamorphosis, a significant acceleration in the measured parameters was seen for the animals raised in conditions of constant light in comparison with those in constant darkness. Those with diurnal lighting were intermediate.
These results suggested that light, or its absence, can respectively stimulate or retard amphibian metamorphosis in late larval stages after the hypothalamo-hypophyseal-thyroid axis has matured. Neither continuous light nor continuous darkness during larval development prevented the transformation from tadpole to frog.     

鲶鱼小窝器官的后期发育及形态的研究

电感官包括结节器官(tuberous organ)和壶形器官(ampullary organ)二大类。前者仅存在于电鱼上,后者则在电鱼及某些非电鱼都有发现。对于淡水鲶鱼而言,其壶形器官又称为小窝器官(small pit organ)。行为实验表明某些鱼类的小窝器官有极高的电敏感性,能检测0.5—0.8 nA/cm~2的电流刺激(Peters,1974;Kalmijn,1976),同时有不少报告描述了它的显微和亚显微结构(Sato,1949,1956,1969;Wachtel,1969;Roth,1969)。但是对这种器官的发育过程的研究报告还不多。     

强壮藻钩虾的繁殖及胚胎发育的形态学观察

强壮藻钩虾隶属于节肢动物门甲壳纲端足目钩虾亚目的一种小型水生生物,在20世纪80年代初由任先秋首次记录并进行形态学描述,主要分布在中国黄海、渤海、东海、日本和北太平洋海岸。强壮藻钩虾主要生活在有机物丰富的海水中并常栖息于大型水草中,可全年在野     

EFFECTS OF CADMIUM ON HOUSEFLY: INFLUENCE ON GROWTH AND DEVELOPMENT AND METABOLISM DURING METAMORPHOSIS OF HOUSEFLY

Abstract The objective of this study was to elucidate the effects of cadmium on housefly, Musca domestica. It is suggested that of cadmium in low concentrations of had little influence on growth and development of housefly. Cadmium was mainly distributed in the digestive tracts of housefly larvae, where the cadmium content was higher than that of other parts. During the metamorphosis of housefly the change trend of the cadmium content was very apparent. The cadmium content increased gradually in larval period, whereas it decreased significantly after polarization. Until the sixth day after emergence, only negligible cadmium was left in adult housefly. All these results demonstrated that the response of housefly to cadmium is an evolution adaptation in natural selection.     

食物中某些营养组分对三突花蛛生长发育的影响

研究食中可溶性蛋白、可溶性糖、总糖、铁、磷以及水等营养组分含量对三突花蛛相对取食量（RCR）和食物利用率（ECI）的影响,并建立这些组分对三突花蛛相对取食量和食物利用率的线性数学模型。