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The Lenadora quarry, located 25 km north of Matale, in central Sri Lanka, exploits dolomitic marble on an artisanal scale. It is located in the Highland Complex but very close to its thrust contact with the Wanni Complex. The rocks have undergone metamorphism to the granulite facies; by analogy with metasedimentary rocks in a similar position south of Kandy, conditions of metamorphism may even have surpassed 900°C and 0.9 GPa. How did dolomitic marble fare in such an ultrahigh-temperature environment? High-resolution large-area image mosaics of imaged polished thin sections were acquired by using both light microscopy and scanning electron microscopy. We focus on fifty areas of interest. As expected, diopside and forsterite porphyroblasts appeared during prograde metamorphism. However, we did not anticipate to see subhedral porphyroblasts of forsterite mimetically replaced by diopside + dolomite. The conversion could have involved a fluid phase or a carbonate melt that had become locally enriched in silica. The presence of a melt accounts for composite calcite + dolomite globules trapped in forsterite. There is no evidence of breakdown products of dolomite, like periclase or brucite. The evidence that a carbonate melt was present is circumstantial; carbonate systems are notorious for erasing telltale evidence of melting. Other minerals encountered in the dolomitic matrix are phlogopite, pargasite, rutile, hydroxylapatite, zirconolite, lakargiite, a magnesiobeltrandoite-like phase, pyrrhotite, and calcite as a minor phase, some of which is of a second generation. Unreplaced relics of forsterite were partially serpentinized at a retrograde stage.

Background: Various forms of least-squares regression analyses are used to estimate average systematic error (bias) and its confidence interval in method-comparison studies. When assumptions that underlie a particular regression method are inappropriate for the data, errors in estimated statistics result. In this report, I present an improved method for regression analysis that is free from the usual simplifying assumptions and is generally applicable to linearly related method-comparison data. Methods: Theoretical equations based on the Deming approach, further developed by physicists and extended herein, were applied to method-comparison data analysis. Monte Carlo simulations were used to demonstrate the validity of the new procedure and to compare its performance to ordinary linear regression (OLR) and simple Deming regression (SDR) procedures. Results: Simulation studies included three types of data commonly encountered in method-comparison studies: (a) constant within-method SDs for both methods, (b) constant within-method CVs for both methods, and (c) neither SDs nor CVs constant for both methods. For all cases examined, OLR produced unreliable confidence intervals of the estimated bias. However, OLR point estimates of systematic bias were reliable when the correlation coefficient was >0.975. SDR produced reliable estimates of systematic bias for all cases studied, but the confidence intervals of systematic bias were unreliable when SDs of methods varied as a function of analyte concentration. Conclusion: Only iteratively reweighted general Deming regression produced statistically unbiased estimates of systematic bias and reliable confidence intervals of bias for all cases.

Clutches of 4 eggs accounted for 64-73% of all clutches laid in 3 yr by a population of Turquoise-browed Motmots (Eumomota superciliosa) in Yucatán, Mexico. The consistently high frequency of 4-egg clutches was associated with only a slight advantage in fledging success relative to clutches of 3 eggs, which ranged in frequency from 11% to 33%. Differences in number of young fledged and proportion of hatchlings fledged were not statistically significant over 3 yr or in any particular year. Clutches of 4 yielded more surviving young in 2 of 3 yr, averaging 2.02 compared to 1.71 for clutches of 3. The proportion of hatchlings that fledged was higher in broods of 3 (overall = 0.67) than in broods of 4 (overall = 0.55) in 2 of 3 yr. The proportion of hatchlings fledged from clutches of 5 (0.36) was lower over 3 yr than that fledged from clutches of 4 or 3. Approximately 40% of nestling mortality in nests that escaped predation was due to starvation. Other known causes included falls from nests and parasitism by maggots.

THE Cave Swallow (Petrockelidon fulva) previously has been thought to be isolated ecologically from other hirundinids in Texas, narrowly restricted in its breeding sites to sinkholes and the twilight zones of caves (Selander and Baker 1957, Whitaker 1959, Baker 1962, Reddell 1967, see Wauer and Davis 1972 for isolated exceptions). Recently its spatial relationships have changed: P. fulva has expanded its breeding niche in the United States to include habitats altered by human activity and has entered into more intimate contact with other swallows. Preliminary to a detailed analysis of distribution, reproductive biology, and interspecific relationships in culvert-nesting Cave and Barn Swallows (Hirundo rustica), this report details their extensive synchronous and syntopic reproduction in south central Texas.

Perturbations apportees par les observateurs a la reproduction d'Hirundo pyrrhonota dans deux Comtes du Texas. Parametres choisis: taille de la couvee, nombre de jeunes eclos par nid, periode d'incubation, periode de station au nid, nombre de petits emplumes par nid, nombre de petits emplumes par rapport au nombre eclos

Alteration of coagulation status and certain clinical chemistry laboratory determinations of 75 adult patients undergoing cardiopulmonary bypass procedures for acquired heart disease was studied during and after surgery. None of the patients was given transfusions of blood or blood components. With hemodilution, the mean hematocrit value dropped from 38% to 28% during the procedure. Fibrin degradation products and euglobulin lysis time were transiently abnormal. Factor V diminished somewhat during the procedure, whereas factors VIII and IX increased after surgery. Clottable fibrinogen values decreased slightly, but increased to an abnormally high value at 24 and 48 hours. Mean value of platelet counts decreased from 194,000 to 144,000/microliter immediately after surgery. Knowledge of expected deviation of coagulation factors and certain clinical chemistry tests following open heart surgery is helpful in evaluating the status of the postoperative patient.

Although the framework of the reproductive pattern is known for most members of the Neotropical family Momotidae, and extensive studies have been conducted ofseveral (Skutch 1945, 1947, 1964, 1971; Orejuela 1977, 1980; Scott and Martin 1983, 1986), nearly all long-term (year-to-year) aspects of individual breeding behavior of motmots remains conjectural. Observations of the activities of several species of motmots evoke the hypothesis that mate and burrow (cavity) fidelity may exist from year to year in this family -Guatemalan Blue-throated Green Motmots (Aspatha gularis) and Costa Rican Blue-crowned Motmots (Momotus momota) excavate postbreeding burrows (separate from but near to those from which their young were fledged) in which, presumably, they breed

Motmots typically excavate burrows in banks and lay their eggs on bare earth in terminal chambers of these b urrows. The works of Skutch (1947), Klaas (1968), and Orejuela (1977) indicate that in much of Middle America, the behavior of the Turquoise-browed Motmot (Eumomota superciliosu) follows this pattern. In areas of the Yucatan Peninsula that possess shallow soils, however, this motmot commonly frequents the vicinity of natural wells or sinkholes (cenotes) and cave entrances during the breeding season (Gaumer 18811882, Klaas 1968, Orejuela 1977, Reddell 1977), using recesses in the limestone walls as sites for egg deposition. Differences among the observations of these authors and others (see also, Paynter 1955) suggest considerable plasticity in the reproductive pattern of this motmot. Here we present data on E. superciliosa taken at yet a different type of breeding site: elevated apertures in the walls and ceilings of rooms of archaeological ruins at Uxmal, Kabah, and Sayil, Yucatan, Mexico. Observations were made at Uxmal on 19 June and 3 and 4 July 1979, and at Kabah and Sayil on 3 July 1979. On all dates, Turquoise-browed Motmots were abundant (at least 50) near The Governor’ s Palace and The Nunnery Quadrangle at Uxmal. Many of the birds were carrying food to nestlings, which were vocalizing in apertures, rectangular and circular in cross section, which had been made by the Maya in the walls and ceilings of both the inner and outer rooms of these structures. Several rooms sheltered more than one pair of motmots. Here, and at Kabah and Sayil, we saw no agonistic behavior or visible manifestation of territoriality. On 3 and 4 July, recently fledged young (as judged by their size and flight ability) were observed at Uxmal; they uttered vocalizations similar to, but softer than, those given by adults. Twice on 3 July, and once on 4 July, an adult was flushed from the same clutch of three (clean) white eggs deposited on a thin layer of fine-particulate breakdown on the floor of a short, broad (approximately 40 cm length, 25 cm width, 14 cm height) hole located 2.5 m above floor level in the inner room of a 2-room complex within The Governor’ s Palace at Uxmal. This observation supports Skutch’ s (1945) judgment that the attribution by Gaumer (18811882) of relatively elaborate nests to well (cenote?)nesting Yucatan Turquoise-browed Motmots was questionable. Together with our sightings of recently fledged young on these dates, this observation also supports the data of Klaas (1968) taken at a bank-burrowing colony near Champoton, Campeche on 9 July 1962 and his hypothesis that these motmots may rear two broods per season. Recent work on this species near Escircega, Campeche, by Orejuela (1977), however, indicates that early July clutches in that area represent late starts and renestings. An additional observation made at Uxmal is of interest in regard to potential helpers at the nest in this motmot: On 4 July, we watched three individuals of similar size (apparently adult, but rectrices were hidden) perched on a rock within 30 cm of each other with prey in their bills; one held a large scorpion. The group appeared to be waiting to enter the chamber from which we watched. Unfortunately, they flushed at the approach of other visitors to the area, and we could not continue observation. I thank James Reddell and Norberto Gonzalez for their assistance.