Two new species of Viola (Violaceae) from the Intermountain West,U.S.A.

Viola lithion andV. franksmithii are rock-dwelling endemics that belong to the North American perennial, caulescent, simple-leaved, blue-, purple-, or white-flowered group of species.Viola lithion, from the White Pine and Pilot mountain ranges of eastern Nevada and adjacent Utah, belongs to sectionChamaemelanium subsectionCanadenses. It most closely resembles the reniform-leaved, Olympic MountainV. flettii, together with which it possibly shares an ancestry with the widespread and allopatricV. canadensis. Viola franksmithii, restricted to the Logan Canyon drainage of the Bear River Range in northern Utah, belongs to sectionRostellatae subsectionRosulantes. It comes closest morphologically toV. howellii of the Coast Range, but likely evolved from the widespreadV. adunca or a common ancestor.     

Freshwater sponges (Porifera: Spongillidae) from Panamá

Aquatic habitats in the Republic of Panamá were examined for freshwater sponges during 21 Feb. to 6 March 1986. Eunapius carteri, Trochospongilla leidyi, and Trochospongilla horrida were found in the northern canal area. This is the first report of E. carteri and T. horrida from Central America, and the first record of E. carteri from the Western Hemisphere. Taxonomic characters used to distinguish T. leidyi and T. horrida from similar South American species are discussed.     

Nutritional criteria in machiguenga food production decisions: A linear-programming analysis

Machiguenga Indians of the Peruvian Amazon, like other low populationdensity, technologically “simple” peoples, produce ample food for a nutritious diet. Assuming that this is an intended outcome of their foodproduction strategy, to what extent is it a labor-efficient solution to the problem of producing a “balanced diet”? A linear-programming model of the “diet problem” is constructed with parameters reflecting the Machiguenga economy, and solutions are computed. These are then compared to observed Machiguenga food production; the degree of fit between model and behavior is examined and reasons for discrepancies are discussed.     

The bull shark (Carcharhinus leucas) and largetooth sash (Pristis perotteti) in Lake Bayano,a tropical man-made impoundment in Panama

Synopsis The Río Bayano in eastern Panama is one of many tropical rivers in which bull sharks (Carcharhinus leucas) and largetooth sawfish (Pristis perotteti) have been known to occur. Since both species can osmoregulate in fresh water throughout life, theoretically, both could survive in landlocked situations for many years.P. perotteti reproduces in fresh water, butC. leucas ordinarily does not, so only the former would appear to have the potential for establishing a breeding stock in such a landlocked freshwater body.The damming of the Rio Bayano and the creation of a large impoundment in 1976 provides a test of the ability of members of both species trapped there to survive and to establish breeding stocks. In 1980 and 1981 three mature femaleC. leucas were found dead in Lake Bayano and three sub-adult femaleP. perotteti were taken by trammel net. These events confirm the ability of both to survive in fresh water for long periods, but the establishment of breeding stocks appears doubtful and the question may not be answered for many years.     

Upper pleistocene human remains from Vindija cave,Croatia, Yugoslavia

Human remains excavated from Vindija cave include a large although fragmentary sample of late Mousterian-associated specimens and a few additional individuals from the overlying early Upper Paleolithic levels. The Mousterian-associated sample is similar to European Neandertals from other regions. Compared with earlier Neandertals from south central Europe, this sample evinces evolutionary trends in the direction of Upper Paleolithic Europeans. Compared with the western European Neandertals, the same trends can be demonstrated, although the magnitude of difference is less, and there is a potential for confusing temporal with regional sources of variation. The early Upper Paleolithic-associated sample cannot be distinguished from the Mousterian-associated hominids. We believe that this site provides support for Hrdli?ka's “Neandertal phase” of human evolution, as it was originally applied in Europe.     

Brachiopod community paleoecology, paleobiogeography, and depositional topography of the Devonian Onondaga Limestone and correlative strata in eastern North America

The Emsian? through early Eifelian Onondaga Limestone of the Appalachian Basin was deposited in a topographic basin and on the carbonate platform which surrounded the basin on the west, north, and northeast. Onondaga strata thin from the platform into the basin. Two sedimentary cycles are present in the sub-Tioga Onondaga of eastern North America. The Edgecliff-Amherstburg represents an interval of transgression, in which epeiric seas spread over much of eastern North America. During the Nedrow-Lucas regression, the interior of the carbonate platform became restricted, resulting in the deposition of evaporites. The Moorehouse-Anderdon transgression continued through the deposition of the Tioga Bentonite, followed by the pre-Speeds-Dundee regression from the craton. Early Eifelian Appalachian Basin Onondaga brachiopod communities, arranged from nearshore to offshore, include the Atrypid-Megakozlowskiella, Atrypid-Levenea, Chonetid, Atlanticocoelia, Ambocoeliid, and Truncalosia Communities. The Onondaga-age Eastern Americas Realm is divided into the Appohimchi Province in the Appalachian Basin and the Michigan Basin-Hudson Bay Lowland Province in the Midwest. The provincial assignment of the James Bay region of Ontario is uncertain; the Eastern Townships of Quebec are near the boundaries both of the two provinces of the Eastern Americas Realm, and of the Eastern Americas Realm and the Old World Realm, the latter realm being probably in the Canadian Maritime Provinces.     

The effect of tunicamycin on development of the mammalian embryonic pancreas

The role of cell-surface glycoproteins in histogenesis of the embryonic rat pancreas was investigated by studying the effect of tunicamycin (TM) on in vitro development. TM has been shown to block glycosylation of asparagine residues in glycoproteins by inhibiting formation of dolichol oligosaccharide intermediates. Exposure of Day 15 pancreatic rudiments to 1.0 μg TM/ml for 15 or 24 hr inhibited [³H]mannose, [³H]glucosamine, and [³H]fucose incorporation by 95, 85, and 90%, respectively, while [³H]leucine incorporation was reduced by 35%. Similar results were obtained with Day 17 rudiments. These trends were confirmed using sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis and fluorography. Inhibition of [³H]monosaccharide incorporation correlated with reduced binding of RCA I-ferritin conjugates to the cell surface and both effects of TM were reversed by reculturing rudiments in medium lacking the antibiotic. Morphologically, TM treatment resulted in a delay in pancreatic histogenesis and this delay correlated with an inhibition of the normal increase in specific activity of amylase, an acinar cell secretory protein. These effects were not mimicked by treatment with cycloheximide at a concentration which inhibited [³H]leucine incorporation to the same degree observed with TM. The percentage of delayed rudiments decreased as reculturing in the absence of TM was extended.     

The North American «Hipparion Datum and implications for the Neogene of the Old World

A large sample of skulls and associated dentitions of Cormohipparion sphenodus (Cope, 1889). new combination, is described from Miocene deposits of Nebraska, Colorado, New Mexico, and California. This species is morphologically more advanced than the most primitive species of the genus, C. goorisiMacFadden & Skinner, 1981, and more primitive than a third and more advanced species of this genus. C. occidentale (Leidy, 1856). In several characters such as configuration of the preobrital fossa, size, hypsodonty, shape of protocone, and complexity of enamel plication, C. sphenodus is morphologically similar, and potentially related to, some Old World Vallesian «Hipparion. In addition, based on radiometric calibration of stratigraphic sequences in Nebraska and California, C. sphenodus spans an interval of time from about 13.6 to 11 Ma. Inasmuch as the Old World «Hipparion Datum is calibrated at about 12 Ma, we conclude that C. sphenodus exhibits the morphological and chronological prerequisites to have been directly ancestral to some of these Old World forms.The hipparion horses apparently were a polyphyletic assemblage of several genera, and their biogeographic and biochronologic history is more complex than classically thought. Several dispersal events involving these horses may have occurred between the New and Old Worlds during the late Miocene.     

Revision du genre LycopodiopsisB. Renault, 1890

The study of imprints of Lycopsida from Permianof the Gondwana has permitted to specify the organisation of the leaf cushions and their variation in the genus LycopodiopsisB. Renault. The presence of a ligula is showed off. The invalidity of the genera Cyclodendron and Lycopodiophloios is demonstrated, and the species refered to these genera must be refered to the genus Lycopodiopsis for which an emended diagnosis is proposed.     

Chemical separation of helper cell function and delayed hypersensitivity responses

Studies were performed to investigate the effects of the immunosuppressive chemical TCDD. Fetal and neonatal rats were exposed to TCDD through maternal dosing (5 μg/Kg) at Day 18 of gestation and on Days 0, 7, and 14 of postnatal life. Another group of neonatal rats were exposed to TCDD through maternal dosing on Days 0, 7, and 14 of postnatal life only. Parameters of cell-mediated and humoral immune function were investgiated. TCDD suppressed delayed hypersensitivity responses and responses to the mitogens Con A and PHA without affecting humoral immune function. Suppression of T-cell function was selective in that helper function was not suppressed. Transfer of primed T-lymphocytes from TCDD treated and non-treated animals into neonatally thymectomized animals confirmed this. Results indicate that delayed hypersensitivity function and helper function reside in distinct T-cell subsets.