Ultrastructural observations on the phoronid nervous system.

abstract：:A novel approach is proposed toward quantifying changes in chaetotaxy during the development of Collembola Symphypleona. The ontogenetic trajectories method applied to the tibiotarsal chaetotaxy of Symphypleona provides a representation of their development. Every seta, through the probability of its presence, can be ...

journal_title：Journal of morphology

authors： Nayrolles P

更新日期：1996-02-01 00:00:00

abstract：:Adult female white-footed mice, Peromyscus leucopus, were exposed to long (LP) or short (SP) photoperiods for 6 weeks (experiment I). Another group of animals was kept for 6 weeks in SP, then injected SC with 30 micrograms prolactin twice daily for 2, 3, 4, or 6 days (experiment II). Ovaries from the mice in both expe...

journal_title：Journal of morphology

authors： Spanel-Borowski K,Bartke A,Petterborg LJ,Reiter RJ

更新日期：1983-05-01 00:00:00

abstract：:From the elongated neck of the giraffe to the elaborate train of the peacock, extreme traits can result from natural or sexual selection (or both). The extreme chelicerae of the long-jawed spiders (Tetragnatha) present a puzzle: do these exaggerated chelicerae function as weapons or genitalia? Bristowe first proposed ...

journal_title：Journal of morphology

authors： Danielson-François A,Sullivan HN

更新日期：2020-10-19 00:00:00

abstract：:Allografts of skin were observed in Chelydra serpentina. The response to these grafts was modified by a previous transplantation of a limb bud at an early embryonic stage. When the same donor was used for all transplants, the first skin graft was accepted by the host. A second skin graft, however, was rejected at abou...

journal_title：Journal of morphology

authors： Yntema CL

更新日期：1974-12-01 00:00:00

abstract：:The mouthparts of female Corethrella brakeleyi and C. wirthi were studied using light and electron microscopy. Mandibles, hypopharynx and labium are highly sclerotized and are modified for obtaining blood meals. All structures were larger in C. brakeleyi than in C. wirthi except mandibular and hypopharyngeal teeth; th...

journal_title：Journal of morphology

authors： McKeever S,Pound JM

更新日期：1979-08-01 00:00:00

abstract：:Developmental studies of the Recent Australian lungfish, Neoceratodus forsteri, show that this species has two sets of functional tooth-bearing bones in the lower jaw of young hatchlings. These coincide with an early stage in the life history when the fish is strictly carnivorous. In N. forsteri, a paired tooth-bearin...

journal_title：Journal of morphology

authors： Kemp A

更新日期：1995-09-01 00:00:00

abstract：:Feeding mechanics of vertebrates depend on physical constraints of the surrounding media, water or air. Such functions are inseparably combined with form. The aim of this study is to show this linkage for the pleurodiran freshwater turtle Pelusios castaneus and, additionally, to point out the major functional and biom...

journal_title：Journal of morphology

authors： Lemell P,Beisser CJ,Weisgram J

更新日期：2000-05-01 00:00:00

abstract：:Among egg-brooding hylid frogs there is much interspecific variation in the degree of development of the young at hatching. In certain species of Gastrotheca the eggs hatch into free-living tadpoles, whereas in others (and in the genera Amphignathodon, Cryptobatrachus, Stefania and Hemiphractus) the eggs hatch directl...

journal_title：Journal of morphology

authors： Wassersug RJ,Duellman WE

更新日期：1984-10-01 00:00:00

abstract：:New schemata of the liver are presented to discuss the combination of the three kinds of liver lobules known until today in a chalk-talk-manner. Terminology is also discussed. Further investigations are needed involving the construction and the vascular pattern of compound lobules of the three individial lobules of th...

journal_title：Journal of morphology

authors： Preuss F,Fricke W

更新日期：1979-11-01 00:00:00

abstract：:The correlation between skin structure and hydrodynamic design of the dorsal fin of the harbor porpoise (Phocoena phocoena) was examined. For the study of fin morphology and geometry, a scheme of sampling representing a two-parameter mesh on the fin surface was used. At each data point the thickness of the epidermis, ...

journal_title：Journal of morphology

authors： Pavlov VV

更新日期：2003-12-01 00:00:00

abstract：:Tardigrada, commonly called water bears, is a taxon of microscopic panarthropods with five-segmented bodies and four pairs of walking legs. Although tardigrades have been known to science for several centuries, questions remain regarding many aspects of their biology, such as embryogenesis. Herein, we used scanning el...

journal_title：Journal of morphology

authors： Gross V,Minich I,Mayer G

更新日期：2017-04-01 00:00:00

abstract：:The gonads from three hermaphrodite species of different invertebrate phyla were studied at the ultastructure level. In the flatworm Dugesia biblica, male germ cells in different stages of development lay in the lumen of testicular follicles surrounded by overlapping parietal cells. The intercellular space formed by c...

journal_title：Journal of morphology

authors： O'Donovan P,Abraham M

更新日期：1987-06-01 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：:Gross lung morphology is examined in representative species from four genera within the order Lagomorpha (Lepus californicus, Sylvilagus nuttalli, Oryctolagus cuniculus, Ochotona princeps), and compared with a representative rodent out-group (Spermophilus richardonsii). Examination of pulmonary morphology reveals seve...

journal_title：Journal of morphology

authors： Simons RS

更新日期：1996-12-01 00:00:00

abstract：:Bristle positions in two rows of bristles on the basitarsus of the second leg of the fruitfly Drosophila melanogaster were analyzed in order to determine the accuracy of bristle placement within these rows. Within each row the positions of the two terminal bristles were found to be approximately equally variable, and ...

journal_title：Journal of morphology

authors： Held LI Jr,Pham TT

更新日期：1983-11-01 00:00:00

abstract：:The development of diet-induced phenotypic differences in numbers of sensilla on the antennae of the grasshopper Schistocerca americana was studied using the exuviae produced at each molt. This made it possible to follow changes within an individual insect. In the first instar, insects had similar numbers of four sens...

journal_title：Journal of morphology

authors： Chapman RF

更新日期：2002-11-01 00:00:00

abstract：:Morphologists and systematists have long suspected that dietary consistency can affect skull and dental form in mammals. We examined plasticity of skull shape and tooth morphology in prairie deer mice (Peromyscus maniculatus bairdii) by feeding mice diets that differed in consistency but not nutritional quality. Shape...

journal_title：Journal of morphology

authors： Myers P,Lundrigan BL,Gillespie BW,Zelditch ML

更新日期：1996-08-01 00:00:00

abstract：:The uptake and retention of radiolabeled estradiol by both the male and female reproductive organs were examined in the baboon. Two male and two female baboons were injected intracardially with 1 microgram/kg body weight of 3H-estradiol and two animals, one male and one female, were injected with both labeled and 100 ...

journal_title：Journal of morphology

authors： Weaker FJ,Sheridan PJ

更新日期：1982-05-01 00:00:00

abstract：:All developmental stages of Tanystylum bealensis are described. This is the first complete developmental series of a pycnogonid species collected from a natural, rather than a laboratory-reared population. Development proceeds through a series of nine instars from egg to adult, with major defining characteristics of t...

journal_title：Journal of morphology

authors： Gillespie JM,Bain BA

更新日期：2006-03-01 00:00:00

abstract：:Spermiogenesis in the South American leptodactylid frog Odontophrynus cultripes was analyzed ultrastructurally. The spermatids undergo morphological modification while still enclosed in microtubule-rich processes of Sertoli cells. Electron-dense plates resembling junctional structures appear in regions at which the sp...

journal_title：Journal of morphology

authors： Báo SN,Dalton GC,de Oliveira SF

更新日期：1991-03-01 00:00:00

abstract：:The chondrocranium is a cartilaginous structure that forms around and protects the brain and sensory organs of the head. Through ontogeny, this skeletal structure may become more elaborate, remodeled and reabsorbed, and/or ossified. Though considerable attention has been given to the formation of the chondrocranium an...

journal_title：Journal of morphology

authors： Daniel J P,Christopher A S

更新日期：2013-01-01 00:00:00

abstract：:Freshwater sponges of the family Spongillidae reproduce sexually through formation of a parenchymula larva. The cytochemical characteristics of parenchymula larval metamorphosis - beginning with the blastula and terminating with the motile escape stage - for the spongillid Eunapius fragilis (Leidy) have been defined u...

journal_title：Journal of morphology

authors： Harrison FW,Cowden RR

更新日期：1975-02-01 00:00:00

abstract：:The orbital Harderian gland of the common tree shrew (Tupaia glis) was investigated at the macroscopic and microscopic levels. In the glands of both sexes only one acinar cell type was found. The cell is characterized by the presence of numerous lipid vacuoles of variable size and by a small number of PAS-positive, el...

journal_title：Journal of morphology

authors： Pradidarcheep W,Asavapongpatana S,Mingsakul T,Poonkhum R,Nilbu-nga S,Somana R

更新日期：2003-03-01 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：:The gross and microscopic anatomy of epidermal glands has been studied in laboratory maintained tokays (Gekko gecko), and house geckos (Hemidactylus bowringii) captured from the wild throughout the year. Annual testicular activity in the house gecko has also been studied. While no significant differences in glandular ...

journal_title：Journal of morphology

authors： Chiu KW,Maderson PF

更新日期：1975-09-01 00:00:00

abstract：:African lungfish (Protopterus) seem unique among osteognathostomes in possessing a potential vomeronasal organ homolog in form of accessory epithelial crypts within their nasal cavity. Many details regarding structural and functional properties of these crypts are still unexplored. In this study, we reinvestigate the ...

journal_title：Journal of morphology

authors： Wittmer C,Nowack C

更新日期：2017-06-01 00:00:00

abstract：:Morphological features of the goldfish caudal neurosecretory system were investigated by means of immunohistochemical localization of urotensins I and II (UI and UII) and electron microscopic examination of the caudal neurosecretory neurons, the urophysis, and the synaptic neuropil. The aim of the work is to provide a...

journal_title：Journal of morphology

authors： Cioni C,De Vito L,Greco A,Pepe A

更新日期：1998-01-01 00:00:00

abstract：:The sequential changes during spermatogenesis in the testis of two species of caecilians, Ichthyophis tricolor (Ichthyophiidae) and Uraeotyphlus cf. narayani (Uraeotyphliidae), of Western Ghats of Kerala, India, were traced using both histological techniques and transmission electron microscopy. The cell nests were as...

journal_title：Journal of morphology

authors： Smita M,Oommen OV,Jancy MG,Akbarsha MA

更新日期：2004-07-01 00:00:00

abstract：:Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep-sea vent endemic species (N...

journal_title：Journal of morphology

authors： Yorisue T,Chan BK,Kado R,Watanabe H,Inoue K,Kojima S,Høeg JT

更新日期：2016-05-01 00:00:00

abstract：:Gross and histological examination of all extant families of turtles revealed that the buccopharyngeal mucosa is morphologically highly varied. The tongues of aquatic species have small lingual papillae or lack them entirely, while terrestrial species have tongues with numerous glandular papillae. The pharynx and the ...

journal_title：Journal of morphology

authors： Winokur RM

更新日期：1988-04-01 00:00:00