Effective implementation of secondary science curricula developed in the last 15 years requires classroom teachers to use inquiry strategies. There has been a great deal of discussion as to the degree to which this transition from a traditional teaching approach to an inquiry approach has actually occurred (Gagnd, 1970), even though new curricula have been available and in use by many teachers for more than a decade (Dillon, 1969; Watson, 1967). Several studies have found little or poor acceptance of inquiry philosophy in terms of actual classroom practices (Amos, 1970;Parakh, 1967).Studies have also revealed that there are many variations in the implementation of inquiry strategies and that these variations are dependent upon the manner and degree to which the teacher has translated the theory into his own philosophy (Gallagher, 1961; Montague &Ward, 1967).The purpose of this study was to develop an instrument to determine the inquiry attitudes of secondary science teachers. Development of the InstrumentEighty-three items of inquiry were identified to form the first instrument based on the following sources: Bruner, 1961; Lee, 1960; McRel-BSCS, 1969; NSTA, 1971; Schwab, 1963; and Steiner, 1970. The items selected refer to three areas: classroom teacher-student interaction, laboratory investigations, and textbooks used. Selection of these items was done according to their relationship to classroom inquiry procedures. An inquiry approach requires secondary science teachers to create teaching situations in which students are stimulated to formulate problems and hypotheses. Students must design their studies, and collect and interpret data. Different answers and experimental results are accepted for discussion. Students are encouraged to participate in classroom discussion and laboratory investigations. They are not told the question's answers or told that only one right answer exists. Students are active in the learning process rather than passive. The teacher is student-oriented rather than subject-oriented. Half of the statements were positively formulated toward inquiry strategy and half negatively. The instrument, Inquiry Science Teaching Strategies (ISTS), used a five-point scale in which a subject responded strongly agree (SA), agree (A),

ANALYSIS OF GENETICALLY kn own material by means of exci sed organ culture techniques should provid e information regarding genetic control of metabolism and growth of such mat erial. There are, for exa mple, a number of instances in which dwarfing is known to have a genetic basis. If roots excised fr om such plants were to sh ow the dwarf condition in culture, their growth und er controlled conditio ns, as compared with th ose showing the normal condition, could be subjected to va rious treatments designed to provide information which might be int erpreted in terms of the nature of genetic control. The purposes of this paper ar e to describe the establishment of several clon es of excised roots from such material which show the dwarf as well as normal condition in culture and to analyze some of the differences between them.MATERIALS AND METHODS.-Rick (1952) has reo ported a single gene mutation for dwarfness in tomat o. He calls this gene wd and describes the plant ca r ry ing it as a wilty dwarf which expresses its phenot ype only under field conditions. Th e gene d", an ext re me dwarf allele at the d locus , has been rep orted by Rick and Butler (1956) . Seed carrying the wd gene and the d" gene ind ependently, as well as compara ble lines carrying the normal alleles were kindly supplied by Dr. Charles M. Rick. Most of the observ ations reported in this paper have been made on the wd and iod" lines.Seeds were surface-sterilized in 1 per cent bromine wat er for ten minutes and allow ed to germinate under sterile conditions on moist filter paper in Petri di shes. When the primary roots were 30-SO mrn, long, 10 mm.-tips wer e excised aseptically and cultured according to standard techniques using White's medium (1943). Fresh weight of roots grown for a given period was obta ined as quickly as possible after pressing them once lightly between the pieces of filter paper. Dry weights were obtained after drying to constant weight in an oven at 105°C. In obtaining dry weights, 10 or more roots were used at each harvest. Nitrogen determinations were made by the micro-Kjeldahl method. Roots grown under standard conditions were killed and fixed in F.A.A. , cleared in 0.5 per cent sodium hydroxide, and length s of epidermal cells at different distances fr om the apex were determined usin g an eyepiece micrometer and a calibrated mechanical sta ge.RESULTS AND DISCUS SION.-Establishment of root clones.-wd and wd+ clone s.-At each planting 80 per cent or more of both wd and tod :" seed germi-lReceived for publication May 12, 1958. This work was supported in part by a gra nt from the University Re search Institute of The Univ ersity of Texas. Thanks ar e du e to Mr, Allan S churr for technical assistance. nat ed. The maximum number of uxl" seed germinated within 6 da ys, while it was 14 da ys before the ma ximum number of wd seed germinated. A few of the seedlings were transferred from the laboratory to the greenhouse, planted in soil and grown to maturity. The io d :" plants wer e extremely uniform but tho se of the usl lin...

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Lee, Addison E. (U. Texas, Austin.) The effects of various substances on the comparative growth of excised tomato roots of clones carrying dwarf and normal alleles. Amer. Jour. Bot. 46(1) : 16‐21. Illus. 1959.—Excised tomato roots carrying the wd gene for dwarfness and its comparable normal allele, wd+, were cultured under various conditions in an effort to provide information as to the physiological differences between the 2 root clones. Two percent is the optimal sucrose concentration for both roots, although wd roots appear to be relatively more tolerant to high sucrose concentration than wd+ roots. The addition of yeast extract, casein hydrolysate, 1, 3‐diphenylurea, and a combination of the last 2 in standard medium fail to improve growth of either wd or wd+ roots. The growth of wd roots is favored by the dark while that of wd+ roots is favored by the light. The addition of IAA to the medium fails to stimulate either type. The effects of eosin added to the medium in various concentrations were studied. High concentrations were inhibitory, but the effect of a concentration of 10‐9 g./ml. provided some evidence of an auxin differential between the two clones of roots. The effects of antiauxins were also investigated, but all of those used reduced the growth of both wd and wd+ roots. It was concluded that although there may be some differences in the auxin metabolism between wd and wd+ roots, it is not likely that this is the cause of dwarfism in the wd roots. Kinetin was found to stimulate both wd and wd+ roots in a concentration of 1.0γ/l. but the stimulation was not differential. Gibberellic acid was found to inhibit both wd and wd+ roots in relatively high concentrations. It had little effect on wd roots in relatively low concentrations, but was inhibitory to wd+ roots even in very low concentrations. Thus these substances appear not to be the cause of the dwarf condition of the wd roots.

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