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Reactions of 1-Chloro-3-buten-2-ol 2955 enins), XI, and in a total synthesis of the sex hormone equilenin, XII. In the latter case the procedures have been refined so that the racemic form of the hormone can be prepared in about 28% over-all yield in eight steps from l-keto-7-methoxy-1,2,3,4-tetrahydrophenanthrene, Ilia. The steps involve formylatioti (step 1) followed by treatment with hydroxylamine (step 2) to produce an isoxazole Va, which is isomerized with alkoxide and methylated (step 3) to give the cyano ketone Vila. Condensation of Vila with dimethyl suc-cinate in the presence of potassium i-butoxide (step 4) affords, in one operation, 15-carbomethoxy-14,15-dehydroequilenin methyl ether, Villa (R' = CHg), which is hydrolyzed (step 5) to the free acid IXa, and decarboxylated (step 6) to give 14,15-dehydroequilenin methyl ether, Xa. Hydrogenation of Xa (step 7) followed by demethylation (step 8) gives df-equilenin XII, which on resolution affords d-equilenin, identical with the natural product.

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appropriate intervals of time, and run into 20 ml of cold dry acetone, and remaining sodium acetate was titrated with 0.004 N hydrochloric acid using a Metrohm potentiograph E 336 A.Plots of log (A" -At) vs. time, where A" and At are titers at infinity and at the given times, respectively, were uniformly linear. The slopes multiplied by -2.303 gave the pseudo-firstorder rate Coefficients.Solvolysis Products from 4-OBs.-The solvents and conditions used are listed in Table II. The concentration of 4-OBs was the same as that used for the rate measurements. The ratios of retained 4-OH and inverted 8-OH in Table II were determined by vpc analysis of the reaction mixture on a Hitachi gas chromatograph Model K-53 equipped with a hydrogen flame ionization detector and a UCON R-15 capillary column; the temperature of the column was 140°and carrier gas was helium at 2 kg/cm2 pressure. The products from trifluoroacetolysis were hydrolyzed by 50% aqueous methanol containing sodium carbonate and then analyzed by vpc.Solvent was evaporated from the hydrolysis mixture under a reduced pressure and the residue was dissolved in ether. The ether solution was washed with aqueous sodium carbonate, dried, and evaporated. Treatment of the residue by thin layer chromatography as described above gave pure samples of 4-OH and 8-OH besides a mixture of hydrocarbons.

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White‐sand forests are patchily distributed ecosystems covering just 5% of Amazonia that host many specialist species of birds not found elsewhere, and these forests are threatened due to their small size and human exploitation of sand for construction projects. As a result, many species of birds that are white‐sand specialists are at risk of extinction, and immediate conservation action is paramount for their survival. Our objective was to evaluate current survey methods and determine the relative effect of the size of patches of these forests on the presence or absence of white‐sand specialists. Using point counts and autonomous recorders, we surveyed avian assemblages occupying patches of white‐sand forest in the Peruvian Amazon in April 2018. Overall, we detected 126 species, including 21 white‐sand forest specialists. We detected significantly more species of birds per survey point with autonomous recorders than point counts. We also found a negative relationship between avian species richness and distance from the edge of patches of white‐sand forest, but a significant, positive relationship when only counting white‐sand specialists. Although we detected more species with autonomous recorders, point counts were more effective for detecting canopy‐dwelling passerines. Therefore, we recommend that investigators conducting surveys for rare and patchily distributed species in the tropics use a mixed‐method approach that incorporates both autonomous recorders and visual observation. Finally, our results suggest that conserving large, continuous patches of white‐sand forest may increase the likelihood of survival of species of birds that are white‐sand specialists.

I. SPACE VALUES OF THE PERIPHERAL RETINA. I. INTRODUCTION, I. Problem. -The size of objects, as they appear to the eye, varies with the position on the retina of the images of the object. Imaged on the fovea, the object appears of one size; imaged on the periphery of the retina, it appears differently. Analogies to this fact are well known in the perception of extent by the various regions of the skin of the bod}'. But such differences in space perception as exist between the temporal and nasal regions of the retinae of the two eyes, are not paralleled by any similar facts in the province of tactual space perception. That these differences which are striking and interesting so easily escape attention, is to be attributed, in part, to the dominance of foveal vision, and, in part, to the absence of objects in the peripheral field, between which comparisons could be made. If, however, two discs of white cardboard, each provided with a black spot on its periphery, be rotated in the field of vision of one eye, in such a manner that the images of the disks fall on widely different portions of the retina, the differences in the size of the orbits described by the two spots, instantly become apparent. Furthermore, if the black spots are attached to movable radii of the discs, so that the area included in the orbit of each spot can be increased or diminished by lengthening or shortening the radius, a convenient measure exists for determining the amount of spatial disparity between one part of the retina and another. Under these conditions, not only differences in size appear, but 69