Sperm morphology of the Eurasian beaver, Castor fiber: an example of a species of rodent with highly derived and pleiomorphic sperm populations.

abstract：:This descriptive electron microscopic study of the blastogenetic medusa development of Podocoryne carnea focuses on the earliest stages of primordium formation, myogenesis, oogenesis and cnidogenesis. The events which take place at the cellular level prior to the formation of stage 1 (Frey, '68), which are characteriz...

journal_title：Journal of morphology

authors： Boelsterli U

更新日期：1977-11-01 00:00:00

abstract：:The king-of-the-salmon, Trachipterus altivelis (Lampriformes), has an unusual set of oral jaws which allow it the ability to protrude the entire upper jaw, containing the premaxilla and the maxilla bones, to extreme distances. Here, we provide a short description of the cranial anatomy and mechanism of jaw protrusion ...

journal_title：Journal of morphology

authors： Ferry LA,Paig-Tran EW,Summers AP,Liem KF

更新日期：2019-12-01 00:00:00

abstract：:Tadpoles of several different genera were fed graded suspensions of uniform polystyrene particles to determine the lower size limit of particles that could be ingested. Certain tadpoles can extract suspended particles as small as 0.126 μ in diameter from the water. In terms of particle size, this is an efficiency comp...

journal_title：Journal of morphology

authors： Wassersug R

更新日期：1972-07-01 00:00:00

abstract：:The larval epithelium of the sea urchin, Lytechinus pictus, consists of squamous cells and bands of columnar epithelial cells bearing cilia. During metamorphosis this tissue undergoes a series of rapid, complex changes. Through the scanning and transmission electron microscope, we describe and analyse these changes. T...

journal_title：Journal of morphology

authors： Cameron RA,Hinegardner RT

更新日期：1978-07-01 00:00:00

abstract：:Spermatogenesis discontinues during both adult reproductive diapause and quiescence in the flightless males of Omorgus freyi. During both types of dormancy, spermatogenesis discontinuity is a dynamic process involving an uninterrupted supply of primary spermatocytes that undergoes partial development and lyses before ...

journal_title：Journal of morphology

authors： Friedländer M,Scholtz CH

更新日期：1993-12-01 00:00:00

abstract：:This study examines the allometric scaling relationships of the cetacean humerus, radius, and ulna. Bone lengths and diameters were measured for 20 species of odontocete and three species of mysticete cetaceans, representing eight of the nine extant cetacean families. The scaling of individual bone proportions (bone l...

journal_title：Journal of morphology

authors： Dawson SD

更新日期：1994-11-01 00:00:00

abstract：:This research was designed to follow up the observation of Thornton and Kraemer ('51) that regressed, denervated limbs of Ambystoma larvae will not regenerate upon reinnervation if all digits on the limbs were not completely resorbed. The object of this experiment was to determine whether the presence of an apical str...

journal_title：Journal of morphology

authors： Carlson BM

更新日期：1977-11-01 00:00:00

abstract：:Slender blindsnakes (Leptotyphlopidae) are known to use a unique feeding mechanism that involves rapid flexions of the tooth-bearing lower jaw. However, the morphology of the leptotyphlopid jaw apparatus has remained poorly studied due to the extremely small size of these snakes. Here I present a detailed description ...

journal_title：Journal of morphology

authors： Kley NJ

更新日期：2006-04-01 00:00:00

abstract：:Septate junctions develop initially just basad from apical junctional complexes at the apical ends of regenerating gastrodermal cells. The first morphological indication of differentiation of the junction is the appearance of gentle undulations of the plasma membranes of apposing cells. Subsequently dense dots develop...

journal_title：Journal of morphology

authors： Hori I

更新日期：1987-06-01 00:00:00

abstract：:The jaw muscle (i.e., masticatory, suprahyoid, and extrinsic tongue) anatomy and mass were examined in four genera of Old World hamsters (cricetine murids), Mesocricetus, Cricetulus, Tscherskia, and Phodopus. The masseter was the largest and most complicated of the muscles examined. In the superficial layer, a few ven...

journal_title：Journal of morphology

authors： Satoh K,Iwaku F

更新日期：2004-04-01 00:00:00

abstract：:Although mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass dire...

journal_title：Journal of morphology

authors： Hess GS,Bauer RT

更新日期：2002-08-01 00:00:00

abstract：:The hypotheses of relationships within Lari (gulls) are highly unstable, and depend on whether morphological or molecular data are examined. Developmental sequence data are thought to contain phylogenetic information, but have never been applied to the problem of avian systematics. In this article, we describe the oss...

journal_title：Journal of morphology

authors： Maxwell EE,Harrison LB

更新日期：2008-09-01 00:00:00

abstract：:The fine structure of the shell and underlying mantle in young juveniles of the articulate brachiopod Terebratalia transversa has been examined by electron microscopy. The first shell produced by the mantle consists of a nonhinged protegulum that lacks concentric growth lines. The protegulum is secreted within a day a...

journal_title：Journal of morphology

authors： Stricker SA,Reed CG

更新日期：1985-03-01 00:00:00

abstract：:The nurse shark, Ginglymostoma cirratum, is an obligate suction feeder that preys on benthic invertebrates and fish. Its cranial morphology exhibits a suite of structural and functional modifications that facilitate this mode of prey capture. During suction-feeding, subambient pressure is generated by the ventral expa...

journal_title：Journal of morphology

authors： Motta PJ,Hueter RE,Tricas TC,Summers AP,Huber DR,Lowry D,Mara KR,Matott MP,Whitenack LB,Wintzer AP

更新日期：2008-09-01 00:00:00

abstract：:Oribatida are one of the main groups of Acari comprising mostly important decomposers in soils. Most species are particle feeders, an exceptional mode of nutrition in Arachnida. Hence, their feeding organs, the gnathosoma, are of special functional interest. We studied nearly all components using scanning and transmis...

journal_title：Journal of morphology

authors： Alberti G,Heethoff M,Norton RA,Schmelzle S,Seniczak A,Seniczak S

更新日期：2011-09-01 00:00:00

abstract：:A table of development (25 stages) for the period of incubation in the pouch was constructed for Gastrotheca riobambae; it can be used to stage embryos of other egg-brooding hylids. Analysis of embryonic weights during incubation shows that the mother does not contribute nutrients, but gases and other factors are prob...

journal_title：Journal of morphology

authors： del Pino EM,Escobar B

更新日期：1981-03-01 00:00:00

abstract：:In Japan Pseudopythina tsurumaru is an up to 10.8 mm-long commensal of the burrowing sea cucumber Protankyra bidentata, whereas in Hong Kong the same species is smaller and associated with the crab Hexapus anfractus, itself a commensal of P. bidentata. Japanese P. tsurumaru is a hermaphrodite tending towards protogyny...

journal_title：Journal of morphology

authors： Lützen J,Jespersen A,Takahashi T,Kai T

更新日期：2004-10-01 00:00:00

abstract：:The ovarian follicles of Ctenosaura pectinata exhibit a clear seasonal cycle in morphology. Early in development, each oocyte is surrounded by a granulosa composed of a single layer of cuboidal or squamous cells and thin thecal layers. As folliculogenesis progresses, the granulosa becomes multilayered and composed of ...

journal_title：Journal of morphology

authors： Uribe MDCA,B GLP,Guillette LJ Jr

更新日期：1996-10-01 00:00:00

abstract：:The flagellum of the thysanopteran spermatozoon has been examined by electron microscopy and computer-aided image analysis. The flagellum consists of 27 microtubular elements that probably are formed as outgrowths from three separate basal bodies. Nine of the elements are normal microtubular doublets that carry dynein...

journal_title：Journal of morphology

authors： Dallai R,Afzelius BA,Lanzavecchia S,Bellon PL

更新日期：1991-09-01 00:00:00

abstract：:The marine priapulid Priapulus caudatus has a voluminous body cavity filled with a blood-like fluid containing erythrocytes and leucocytes (amoebocytes). The hematocrit of animals weighing 0.5-14 gm was 2-10%. The erythrocytes contain a hemerythrin blood pigment. The structure of the coelomocytes was studied by light ...

journal_title：Journal of morphology

authors： Mattisson A,Fänge R

更新日期：1973-07-01 00:00:00

abstract：:Testicular samples were collected to describe the ultrastructure of spermiogenisis in Alligator mississipiensis (American Alligator). Spermiogenesis commences with an acrosome vesicle forming from Golgi transport vesicles. An acrosome granule forms during vesicle contact with the nucleus, and remains posterior until m...

journal_title：Journal of morphology

authors： Gribbins KM,Siegel DS,Anzalone ML,Jackson DP,Venable KJ,Rheubert JL,Elsey RM

更新日期：2010-10-01 00:00:00

abstract：:The silk production systems of several specimens representing at least three species of the mygalomorph genus Euagrus were examined by dissection and by a variety of absorption and fluorescent histochemical techniques. The intrageneric variation is primarily restricted to gland number, with larger numbers of glands in...

journal_title：Journal of morphology

authors： Palmer JM

更新日期：1985-11-01 00:00:00

abstract：:Mature spermatozoa from spermathecae of founding queens were obtained from 5 species of ants, representing the major subfamilies Myrmicinae (Acromyrmex versicolor, Crematogaster sp.) and Dolichoderinae (Tapinoma sessile, Conomyrma insana, Conomyrma wheeleri). The ultrastructure of ant spermatozoa has many features in ...

journal_title：Journal of morphology

authors： Wheeler DE,Crichton EG,Krutzsch PH

更新日期：1990-12-01 00:00:00

abstract：:This investigation describes the morphogenesis of the type I pneumocyte from the neonatal stage to the age of 3 months. Cells lining subpleural air spaces were photographed from electron microscopic serial sections and a three-dimensional representation of each cell was obtained by transferring the contours of the cel...

journal_title：Journal of morphology

authors： Mercurio AR,Rhodin JA

更新日期：1984-11-01 00:00:00

abstract：:To our knowledge, this paper presents the first description of neuroendocrine complexes in invertebrates. Neuroendocrine complexes have been identified in the lamina propria of the snail gut by light microscopy using Giemsa-stained, deplasticized sections and by electron microscopy. Silver impregnations and immunocyto...

journal_title：Journal of morphology

authors： Alba Y,Villaro AC,Sesma P,Vázquez JJ

更新日期：1989-03-01 00:00:00

abstract：:Non-innervated macrotrichia and microtrichia, thick-walled chemoreceptors and three kinds of thin-walled chemoreceptors are present on the antennal flagellum of Frenesia missa. One of the thin-walled receptors, the plate organ, is of a type not previously recorded for any insect. About four times as many plate organs ...

journal_title：Journal of morphology

authors： Slifer EH,Sekhon SS

更新日期：1971-11-01 00:00:00

abstract：:The crocodilian naris is regulated by smooth muscle. The morphology of this system was investigated using a combination of gross, light microscopic, and micro-CT analyses, while the mechanics of narial regulation were examined using a combination of Hall Effect sensors, narial manometry, and electromyography. Alligato...

journal_title：Journal of morphology

authors： Klassen M,Adams J,Cramberg M,Knoche L,Young BA

更新日期：2020-06-01 00:00:00

abstract：:The locomotory system of Solifugae is distinct from that of other Arachnida in several ways. Only three pairs of legs are involved in locomotion, while the first pair function as sensory appendages. Morphologically, the proximal region of the locomotory system in Solifugae is characterized by fused coxae. Within the p...

journal_title：Journal of morphology

authors： Runge J,Wirkner CS

更新日期：2020-12-01 00:00:00

abstract：:Previously we showed that type XII collagen (col XII) is highly upregulated in the regenerating newt (Notophthalmus viridescens) forelimb. Here, using immunohistochemistry and in situ hybridization, we studied the pattern of expression of col XII during early stages of adult newt tail regeneration. The results show th...

journal_title：Journal of morphology

authors： Wei Y,Tassava RA

更新日期：1996-11-01 00:00:00

abstract：:An ultrastructural study was carried out on the secretory activity of the ectal mandibular gland in the wasp Polistes dominulus (foundress and worker females as well as males). Secretory activity in foundresses proceeds slowly during hibernation and early spring, becoming prominent in late spring and then falling shar...

journal_title：Journal of morphology

authors： Fortunato A,Turillazzi S,Delfino G

更新日期：2000-04-01 00:00:00