La revista de zoología experimental . ing longevidad de las personas y, en parte, al hecho de quelas más favorables fueron frecuentemente experimentado withlonger animales de un ambiente menos favorable. Las determinaciones de aproxi-madamente la primera mitad de los animales fueron realizados en el plan de laprimera tipo de experimento, mientras que el resto fueron transportados outaccording al esquema utilizado en el segundo tipo. A partir de las cifras que figuran en las columnas F y G de la tabla 2, es evidente que hay una fuerte preponderancia dela d valores positivos sobre los negativos. La proporción de los dos isstrikingly mostrado en la Frec.

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The Journal of experimental zoology . ing longevity of individuals and in part to the factthat more favorable animals were frequently experimented withlonger than less favorable ones. The determinations of approxi-mately the first half of the animals were made on the plan of thefirst type of experiment, while the remainder were carried outaccording to the scheme used in the second type. From the figures presented in columns F and G of table 2, it is evident at once that there is a marked preponderance ofthe positive d values over the negative. The ratio of the two isstrikingly shown in the frequency polygon (fig. 11) Since thenumber of d values varied considerably with the individual, due 382 DWIGHT E. MINNICH to the causes noted above, I have included in the polygon onlythe first four values for each bee, thus giving equal weight toevery animal. Of the total two hundred and seven^ values rep-resented in the polygon, 81.16 per cent are positive, whereasonly 18.84 per cent are negative, a ratio of over 4 to 1. 18.84% 81.16%. -16-14-12-10-8 -6 -4 -2 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Degrees per cm. Fig. 11 Frequency polygon of the first four d values of fifty-two bees. The-negative values are represented by the shaded areas; the positive values, by theclear areas. In the case of one bee it was possible to include only three values for d, because of a missing record. See Table 2 (Appendix), bee no. 45. PHOTIC EEACTIONS OF HONEY-BEE 383 The objection might be raised that although the majority ofvalues of d are positive, a number of them are too small to be ofany significance. It is true that differences of the order of l°/cm.or less might easily be attributed to slight errors in tracing thecourse of a bee. Errors in recording, however, are as likely tooccur in one direction as the other. Such is not the case withthese small values. The class of d values betwen 0 and —2°/cm.contains but fifteen, while the class of 0 to +2°/cm. numberstwenty-nine—nearly twice as m

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• bookcentury1900
• bookdecade1910
• booksubjectzoology
• bookyear1919