ANGIOSPERM WOOD FROM THE UPPER CRETACEOUS OF CENTRAL CALIFORNIA: PART I

This paper is the first in a series about a collection of 40 Upper Cretaceous woods from central California. The wood is in the form of fragments of stems and roots embedded in nodules of collophane rich in microorganisms, pollen, and spores. Two new species are described: Ulminium pattersonensis and Ulminium mulleri. Evidence presented indicates that these two specimens are similar to woods of the Lauraceae and fall well within the range of variation of woods of that family. Because the taxonomy of the Lauraceae is in need of revision, meaningful comparisons of fossil plant parts with modern taxa were found to be unfeasible.     

ANGIOSPERM WOOD FROM THE UPPER CRETACEOUS OF CENTRAL CALIFORNIA: PART II

Three species of fossil wood representing two genera are described. The specimens are from a collection of woods from the Upper Cretaceous Panoche formation of central California. Tetracentronites panochetris sp. nov. resembles angiosperm wood in ray structure and vascular pitting but lacks vessels. Plataninium platanoides sp. nov. is similar to the wood of Platanus, and the evidence presented points to a direct relationship. The resemblance between Plataninium cali-fornicum sp. nov. and the woods of certain Icacinaceae is discussed, but evidence of relationship is inconclusive.     

A NEW CONIFER FROM THE UPPER CRETACEOUS OF CENTRAL CALIFORNIA

Stems with inner bark, wood, pith, and leaves from the Upper Cretaceous (Maastrichtian) of central California are described. The name Margeriella cretacea gen. et sp. n. is assigned to the fossils. The leaves are long, narrow, spirally arranged, and each contains three resin canals, a thick vascular sheath, and a dense mesophyll. Only first-year wood is present in the stem. The large pith is composed of large cells among which are scattered clusters of even larger darkly colored cells. Leaf epidermis and wood characters suggest affinities with the Taxodiaceae, but the structure of the pith and the internal structure of the leaves have no counterpart among modern or known fossil members of that family. The fossil is regarded as an extinct form possibly belonging to the large taxodioid complex thought by some workers to have existed in the Mesozoic.     

TAXODIACEOUS BARK FROM THE UPPER CRETACEOUS OF ALBERTA

The structure of a piece of silicified bark of Taxodioxylon gypsaceum from near Medicine Hat in Southern Alberta is described. The fossil specimen probably came from Upper Cretaceous beds. The fossil shows affinities with the bark of modern Sequoia. Vectia luccombensis Stopes (1915) from the Lower Greensand (Aptian) of England probably constitutes an isolated piece of taxodiaceous bark, similar to the inner bark of the Alberta specimen.     

PERMINERALIZED PINACEOUS LEAVES FROM THE UPPER CRETACEOUS OF HOKKAIDO

Three fragments of fascicles of a possible five-needle pine are described from the Upper Cretaceous Yezo Group (Santonian/Senonian) of Hokkaido. Specimens from the Omakizawa, Oyubari, Yubari City, the Koyanozawa, Ikushumbetsu, Mikasa City, and the Sankebetsugawa, Haboro are preserved in calcium carbonate nodules containing abundant ammonites. Leaves borne in apparent fascicles of five measure 0.7–0.8 mm in radial and 0.8–1.0 mm in tangential diam and are represented by short fragments of isolated needles. Thick-walled epidermal cells on these amphistomatic leaves resemble the underlying uniform hypodermis. Two external resin canals are situated near the lateral corners toward the adaxial surface. Only slightly plicate mesophyll cells in a layer one to two cells thick border on an elliptical endodermis with thickened outer cell walls. Two to three layers of transfusion tissue surround the double vascular strand. Two vascular bundles are separated by one cell layer of sclerenchyma fibers. Small patches of abaxial and adaxial sclerenchyma fibers have also been observed. Leaves most closely resemble those of Pinus leiophylla Schl. et Cham. Subgenus Pinus, Section Pinea, Subsection Leiophyllae and P. montezumae Lamb. Subgenus Pinus, Section Pinus, Subsection Ponderosae and are described as a new species P. hokkaidoensis sp. nov. Stockey and Ueda. Close anatomical comparisons are made with this leaf and previously described permineralized Upper Cretaceous pine needles from Hokkaido and eastern North America.     

NEW TAXODIACEOUS SEED CONES FROM THE UPPER CRETACEOUS OF NEW JERSEY

Nephrostrobus cliffwoodensis gen. et sp. nov., Nephrostrobus bifurcatus sp. nov., and Rhombostrobus cliffwoodensis gen. et sp. nov. are described based on anatomical studies of seed cone fragments from the Upper Cretaceous Magothy Formation of New Jersey. These species belong to the Taxodiaceae. As in Sequoia, Sequoiadendron. and Metasequoia, the vascular strands supplying the scale and bract in Nephrostrobus are about equal. These vascular strands are arranged in a reniform pattern resembling that found in Metasequoia, but the orientation differs by 180 degress. Nephrostrobus cliffwoodensis and Nephrostrobus bifurcatus differ from each other in the branching of the complex trace and associated resin canals. Rhombostrobus cliffwoodensis resembles Cunninghamia in the arrangement of vascular strands and associated resin canals in its bract-scale complexes. However, the relative amount of bract and ovuliferous scale making up the complex is more like that in Sequoia. This combination of cone features does not occur in any of the extant genera. Nephrostrobus and Rhombostrobus are not considered to be ancestral to any of the extant taxodiaceous genera, but are extinct members of an ancestral complex from which the extant genera were derived.     

松辽盆地晚白垩世介形类古生态学

通过化石组合和岩性指标分析松辽盆地上白垩统自下而上青山口组—姚家组—嫩江组一段介形类的古生态学。青山口组盐度具有偏咸性、微咸性到半咸性的变化,32个介形类种以栖居于温暖湿润气候带的浅湖微咸水类型占绝对优势,水体清澈安静,有机质丰富,底质为泥等细粒沉积物(个别的为粉砂沉积物),宜于介形类动物群生长且有利于壳体完好保存;其次为生活于半咸水的深湖—半深湖类型,底质为泥。姚家组—嫩江组一段见23个介形类种,栖居于温暖半湿润气候带,以半咸水的深湖、半深湖—浅湖区的类型为主,多泥底,偶见粉砂质底;其次为微咸水的浅湖—三角洲前缘型,泥或粉砂质底;仅3个种生活于温暖湿润的粉砂质底淡水浅湖区。温暖湿润的淡水三角洲分流平原带则难以产出介形类化石。     

上扬子区奥陶系Nemagraptus gracilis 笔石带的几丁虫

作者系统描述了在重庆城口廖子口和宜昌分乡普溪河奥陶系庙坡组Nemagraptusgracilis笔石带中发现的几丁虫化石,共7属9种。由于此前对该层位的几丁虫研究较少,因此本次所发现的几丁虫化石具有重要的生物地层意义。     

PETRIFIED CONES AND NEEDLE-BEARING TWIGS OF A NEW TAXODIACEOUS CONIFER FROM THE EARLY CRETACEOUS OF CALIFORNIA

Ovulate cones identified as Abietites ellipticus Fontaine, from the Early Cretaceous of northern California, have been reinvestigated. Rather than being preserved as imprints as originally described, the fossils are petrified. Two cones are attached to needle-bearing twigs. The organs are similar to those of the living Cunninghamia lanceolata. However, the scale portion of the bract-scale complex of the fossil cones is situated close to the bract apex, while that in modern Cunninghamia cones is midway between the bract base and apex. This plus other structural differences warrant treatment of the material as a new species of Cunninghamiostrobus Stopes and Fujii.     

CONIFER WOOD FROM THE UPPER JURASSIC OF UTAH PART I: XENOXYLON MORRISONENSE SP. NOV.

A new species of conifer wood, Xenoxylon morrisonense, is described from the Morrison Formation on the Colorado Plateau. It is compared with other species of Xenoxylon, with X. latiporosum being the closest. Xenoxylon morrisonense differs from X. latiporosum in its marked indentations, simple pits on the horizontal and tangential walls of ray cells, absence of crassulae, presence of wood parenchyma, and thin borders on podocarpoid type crossfield pits. The origin of the septa in the tracheids is summarized, and the possible affinity of Xenoxylon with the Podocarpaceae is considered.     

内蒙古二连盆地早白垩世巴彦花群被子植物花粉

内蒙古二连盆地早白垩世巴彦花群含有类型丰富、保存精美的被子植物花粉。本文利用光学显微镜观察和扫描电镜观察相结合的方法,对这些花粉类型进行了较详细的研究。研究结果表明,巴彦花群的被子植物花粉主要由属于金粟兰科的Hammenia和Singhipollis,悬铃木科/金缕梅科的Tricolpites以及亲缘关系不明的Polyporites组成。这一被子植物花粉组合面貌指示的地质时代为中晚阿尔必期(Albian)。据相关现生植物的地理分布及煤夹层的存在,推测在早白垩世晚期二连盆地处于湿润的亚热带气候环境中。     

吉林省中部早白垩世泉头组-原始鸟脚类恐龙

报道了在松辽盆地白垩纪沉积中首次发现的原始鸟脚类恐龙化石,并根据其头部特征建立一新属新种——娇小长春龙(Changchunsaurus parvus gen.etsp.nov.)。化石产于吉林省公主岭市刘房子镇山前泉头组上部紫红色含砾泥质砂岩中,同一层位还产有兽脚类、鳄类、恐龙蛋、哺乳类等化石。娇小长春龙是一种混合了原始的和衍生性状的小型鸟脚类恐龙。它具有某些比多数鸟脚类和头饰龙类要原始的特征,例如,5颗前上颌齿、前上颌骨吻部只有很短一段齿缺、前上颌骨与上颌齿之间的间隙较小、颊齿两侧的釉质对称、前上颌骨腹侧边缘与上颌骨腹侧边缘基本处于同一水平线等。同时,娇小长春龙也具有一些与真鸟脚类类似的进步特征,比如眶前孔小、外下颌孔缺失。娇小长春龙具有颧骨突,这在鸟脚类恐龙中较为罕见,它的颧骨突表面具有鲕状构造,这一特征未见于其他已知鸟脚类。娇小长春龙的前齿骨形态与角龙类接近,腹支明显长于侧支,前齿骨与齿骨的愈合方式同角龙类相似。娇小长春龙的确切系统分类位置需要进一步的工作来确定。     

广西合浦盆地晚白垩世和古新世的介形类化石

本文报道合浦盆地晚白垩世乌家组和古新世上洋组的介形类化石14属23种(描述1新种),可划分两个化石组合:(1)Rhombicypridea quadrata-Heterocypris hepuensis-Limnocythere sinuata组合,属于Talicypridea动物群,产于乌家组,时代为晚白垩世;(2)...     

蒙古戈壁上白垩统的暴龙类额骨(英文)

记述了发现于蒙古戈壁查干泰格地点的一块额骨。短的眶缘和矢状脊的存在等特征表明,该标本属于暴龙超科。查干泰格地点出露的地层被认为属于森诺曼-桑托期的巴音沙拉组,新材料的发现为上白垩统下部非常稀少的暴龙类恐龙记录增添了新的内容。     

中国上白垩统窃蛋龙科一新属种(兽脚类:窃蛋龙类)(英文)

根据可能发现于江西赣州晚白垩世南雄组地层中一件标本报道了窃蛋龙科一新属种——斑嵴龙。新标本具有以下不同于其他窃蛋龙属种的特征:由前颌骨和鼻骨形成的脊冠具有阶梯状的后端,表面有两个纵向的沟槽和许多倾斜的条痕;外鼻孔延长,其后侧与眶骨相近;翼骨腭骨支背缘有一深窝;齿骨后背缘有纵向沟槽;上隅骨前背缘有小结节。斑嵴龙腭部和下颌的一些特征不同于窃蛋龙科的其他属种,但近似于更原始的窃蛋龙类。这些特征表明斑嵴龙代表窃蛋龙科中相对原始的一个属种。这一系统发育假说得到了定量的系统发育分析的支持。斑嵴龙的发现不仅增加了晚白垩世窃蛋龙科的分异度,而且为这一类群的特征演化提供了重要信息。     

A REVIEW ON THE STUDY OF EARLY CRETACEOUS ANGIOSPERM POLLEN IN CHINA

The origin and early evolution of angiosperms is one of the most important topics in the field of botany. During the recent twenty years, the theory on Pre-Cretaceous origin of angiosperms was criticized by Scott et al. (1960),Hughes (1976) and others. Palynological data show that the monosulcate pollen possibly bearing an affinity to angiosperms such as Clavatipollenites first appeared from     

浙江天台盆地上白垩统赤城山组长形蛋科一新蛋属

浙江天台盆地上白垩统赤城山组发现一新的恐龙蛋类型。依据蛋化石形态、大小和蛋壳柱状层生长纹呈波浪形等特征,将其归入长形蛋科(Elongatoolithidae)。这枚恐龙蛋的蛋壳外表面具网状纹饰,蛋壳锥体层与柱状层界线明显,二者厚度之比近1:2,气孔道细而直,这些特征区别于其他长形蛋科的成员,因此,建立一新的蛋属、蛋种:网纹副长形蛋(Paraelonga-toolithus reticulatus oogen.et oosp.nov.),代表晚白垩世早期长形蛋科的新成员。     

辽宁晚侏罗世～早白垩世一长颈双弓类爬行动物(英文)

初步记述了采自辽西凌源地区晚侏罗世～早白垩世义县组一新的双弓类水生爬行动物化石材料,并确立其为、新属新种──凌源潜龙（Ｈｙｐｈａｌｏｓａｕｒｕｓ　ｌｉｎｇｙｕａｎｅｎｓｉｓｇｅｎ．ｅｔ ｓｐ．ｎｏｖ．）。化石产于凌源大王杖子乡范杖子村义县组合火山灰的灰白色湖相页岩中,与狼鳍鱼（Ｌｙｃｏｐｔｅｒａ）共生。 凌源潜龙的正模是一具几乎完整、保存完好的化石骨架,包括近乎完整的头骨、下颌骨和头后骨骼,仅尾椎有少量丢失,标本上主要显露腹面骨骼（中国科学院古脊椎动物与古人类研究所标本编号Ｖ１１７０５）。其与水生爬行类Ｃｈｏｒｉｓｔｏｄｅｒｅｓ共有特征包括平凹型脊椎,３个荐椎,背肋肿大,肢骨下节远短于上节,腕骨和跗骨弱骨化。凌源潜龙主要鉴别特征为：相对身体比例,头骨较小;颈部大大加长,颈椎１９个;显著肿大的背肋呈Ｓ型;超过２０组腹肋,每组由３段组成,而对应每一椎体有２～３组腹肋;第Ⅲ、Ⅳ　骨长度基本相等,第Ｖ　骨不为钩状。 凌源潜龙所具有的异乎寻常的长颈与三叠纪海相幻龙类（Ｎｏｔｈｏｓａｕｒｓ）有相似的特征。其所具有的相对小的头骨,尖的吻部,似针状的牙,特殊的长颈及其埋藏特征反映该动物为适应湖泊环境的食鱼性动物。 凌源潜龙是迄?     

THE DISTRIBUTION AND ABUNDANCE OF DEEPWATER MACROALGAE IN CENTRAL CALIFORNIA

Silvetia compressa ( J. Agardh) Serrão et al. is a common member of the upper intertidal fucoid community on the Pacific coast of America from Humboldt County, California, to Punta Baja, Baja California, Mexico. A relatively narrow range of morphological variability is exhibited by most mainland populations, regardless of latitude, but some mainland populations and all insular populations participate in a complex pattern that we have attempted to analyze. A few populations on the Monterey Peninsula in which the fronds are atypically delicate were described by Setchell & Gardner as f. gracilis , to which was assigned a population from Santa Catalina Island. After comparing populations from various parts of the range of the species, including all of the Channel Islands, we conclude that two subspecies may be recognized. In subsp. compressa , which includes f. gracilis as a growth form and occurs chiefly on the mainland, the frond is robust with long tapered receptacles. In the variant subspecies, which is chiefly insular but also occurs on the coast of northern Baja California, the typical frond has slender axes as in f. gracilis , but is more densely branched and has short ellipsoidal receptacles. Comparison of nucleotide sequences from the ITS regions of rDNA revealed an identical pattern for subsp. compressa from Baja California and central California, including populations assignable to f. gracilis. By contrast, the pattern for the variant subspecies differed by 2 bp (0.3%) from that of subsp. compressa.