The Mt. Messenger Formation exposed along the coastline of the Taranaki Peninsula contains flat-laminated, very-fine to fine-grained sands inlerbedded with bioturbated silt and silty claystone. These beds are typically over 5 cm thick and are the result of high-velocity turbidity currents which allow for good textural sorting and preservation of excellent reservoir-quality sands. Beds less than this thickness, as well as upper parts of many turbidites, typically contain features suggesting reworking, winnowing, and remolding by bottom currents. This winnowing effect is responsible for the good to excellent reservoir properties of the thin, poorly consolidated, well-sorted, very fine-grained lithic arenites. Mt. Messenger sands were deposited on a depositional slope in lower to upper bathyal water depths which was the site for these transforming bottom currents. The Mt. Messenger overlies Mohakatino, Ferry, and Tawariki sandstones and siltstones which were the initial deepwater sediments in the basin. These sandstones are lithic-rich and fine to medium-grained. The beds are typically massiveappearing but locally contain dewatering features, typical ‘classic’ turbidites (graded beds, slurry or low-density turbidity current tops), and were deposited as thick sheet-like bodies on the basin floor. Winnowing of the sandstones did not take place on a large scale and hence reservoir quality is invariably poor to moderate. The mica stilpnomelane in the sands is common; this mineral is restricted areally to low-grade regionally metamorphosed sediments and associated veins, most notably to the schists of western Otago, New Zealand, on the northwestern part of the south island The occurrence of this mineral has important implications as to the source of the Mt. Messenger sediments in the North Taranaki area (transport was from south to north from the South Island).

The courtship display of the male golden-collared manakin (Manacus vitellinus) of Panamanian rainforests is noteworthy for several types of whipcrack-like sounds created by a rapid overhead¯ip of the wings. We have hypothesized that this courtship behavior, which is not performed by females, is associated with steroid-sensitive and sexually dimorphic neuromuscular systems. Presumably, muscles creating the motion of the wingsnap in males are specialized for greater force generation and speed of contraction. We tested this hypothesis by examining mass, ®ber diameter, metabolic enzyme activity, and myosin isoform expression in several muscles of male and female manakins and in both sexes of a non-wingsnapping bird, the zebra ®nch (Taenopygia guttata). We have identi®ed three wing muscles, the scapulohumeralis caudalis, the supracoracoideus, and the pectoralis major, that di er in one or more of these characteristics across sex and species, suggesting they are specialized for faster contraction and greater force production in male manakins. These muscles normally function to raise and lower the wings during¯ight. As this movement is the principal motion of the wingsnap, these adaptations presumably underlie the performance of the wingsnap display. Keywords Bird á Courtship á Myosin á Acoustic signals á Sexually dimorphicAbbreviations a-GPD a-glycerophosphate dehydrogenase á Itb m. iliotibialis lateralis á IHC immunohistochemistry á NADH nicotinamide adenine dehydrogenase á OD optical density á Pec m. pectoralis á Sc m. supracoracoideus á SH m. scapulohumeralis caudalis

Sixteen penecontemporaneously deposited mudrock‐sandstone pairs ranging in age from Devonian to Cretaceous were treated chemically to isolate the quartz and chert fraction from the other constituents of the rocks. The amount of crystalline silica was determined from the chemical treatments; its size distribution was determined using a combination of normal and Micro Mesh sieving and settling tube analysis; the crystalline silica coarser than 10 μu was examined petrographically to determine the amount of chert. Percentages of crystalline silica in the mudrocks range from 6·7 to 46·7 % and average 27·6 (σ= 10·7). Mean grain size ranges from 4·4 φ to 7·3 φ and averages 6·1 φ. The crystalline silica fraction is a poorly sorted medium to fine silt consisting of one‐eighth sand, six‐eighths silt, and one‐eighth clay size sediment. Percentage of crystalline silica and mean size of crystalline silica in the thirty‐two mudrocks and sandstones are positively correlated; r= 0·685, which is significant at the 99 % level. The best fit linear regression line is: Y= 102·7–11·3X. Extrapolation of the regression line indicates that, on the average, crystalline silica is lacking in mudrocks in grain sizes finer than 9·1 φ (1·μm), a result consistent with observations by clay mineralogists. The crystalline silica fraction of both the mudrocks and associated sandstones averages 4% chert in the >10 μm portion. There is no correlation between the mean grain size of the crystalline silica and the percentage of chert in it.

Vaterite, a CaCO3 polymorph, is a rare mineral that is said to be metastable under all known conditions. According to the literature, vaterite precipitated from carbonate solution recrystallizes spontaneously to calcite or aragonite. Yet vaterite has been identified in hard tissues of organisms, in gallstones, in contact metamorphic aureoles, in zones of thermal metamorphism, in a meteorite, and in cone-in-cone concretions. Newly precipitated vaterite has formed at the expense of carbonate rock in drilling fluids in wells of New York, Michigan, Nevada, Texas, and New Zealand. Petrographic examination reveals a light brown core of CaaSiO5 surrounded by a colourless rim of vaterite. The ~lSOpo a of New York vaterite is -12.4%o and that of the Michigan vaterite is -17.67/0o, which reflect the oxygen isotopic composition of meteoric freshwater used in drilling. The ~13CpD B value of --19.27/oo for New York vaterite and that of -17.67/oo for Michigan vaterite suggest that natural gas dissolved original carbonate in the subsurface. Drilling records from both wells indicate that natural gas was released into the drilling muds from the formations exposed at the time vaterite was encountered. Crossplots of the oxygen and carbon isotopic ratios overlap those of spurrite rocks in thermal metamorphic zones in Israel. A C-14 radiocarbon analysis of the Michigan vaterite gave an age of 953 + 39 yr. BP. 88.8__+0.6% is modern carbon and 11.2% is dead carbon. Hence this carbon, and therefore the vaterite, is essentially modern. A sample of the New York vaterite yielded a modern age.

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