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The magnitude of discrepancies between agency and state data on volume ofstatefunded mental health services is sample estimated for one state. Some explanations for these discrepancies, in terms of bureaucratic problems and of agencies'efforts to circumvent the effects of these problems on their statistics, are developed from correlations of volume discrepancies with ancillary agency variables.

Accurate and precise determinations of tin in geological materials are needed for fundamental studies of tin geochemistry, and for tin prospecting purposes. Achieving the required accuracy is difficult because of the different matrices in which Sn can occur (i.e. sulfides, silicates and cassiterite), and because of the variability of literature values for Sn concentrations in geochemical reference materials. We have evaluated three methods for the analysis of samples for Sn concentration: graphite furnace atomic absorption spectrometry (HGA-AAS) following iodide extraction, inductively coupled plasma atomic emission spectrometry (ICP-OES), and energy-dispersive X-ray fluorescence (EDXRF) spectrometry. Two of these methods (HGA-AAS and ICP-OES) required sample decomposition either by acid digestion or fusion, while the third (EDXRF) was performed directly on the powdered sample. Analytical details of all three methods, their potential errors, and the steps necessary to correct these errors were investigated. Results showed that similar accuracy was achieved from all methods for unmineralized samples, which contain no known Sn-bearing phase. For mineralized samples, which contain Sn-bearing minerals, either cassiterite or stannous sulfides, only EDXRF and fusion ICP-OES methods provided acceptable accuracy. This summary of our study provides information which helps to assure correct interpretation of data bases for underlying geochemical processes, regardless of method of data collection and its inherent limitations.

Greenbug, Schizaphis graminum (Rondani), infestations are common on wheat in the High Plains of Texas. During the past several years the senior author has noted that adult greenbugs collected from wheat in the field were larger than adult greenbugs reared on wheat indoors. He has also suspected a difference in their size and fecundity after rearing them under different indoor environments. Smirnov and Samokhvalova (1955) stated that a change of host will influence the reproduction, growth, and size of aphids. The greenbug occurs on several different host plants. Daniels (1960) listed 20 species of grass on which greenbugs fed and reproduced. He noted that greenbugs maintained heavier populations on western wheat grass, Agropyron smithii (Rydb.), than on the other grasses and that they remained on it throughout the summer. Randolph and Garner (1961) reported that greenbugs attack grain sorghum as well as small grains.