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tokens: Figure 10 that their N/H ratios are also some of the lowest in the dwarf galaxy sample. However, as shown in Figure 9 , their N/O ratios cover the range of N/O ratio values of all the dwarf galaxies studied. This is consistent with the expectation that nitrogen behaves as a primary element for galaxies with low and moderate metallicities. Details of these 21 dwarf galaxies with extremely low metallicities are listed in Table 3 , including their gas-phase chemical abundances. 6. Conclusions The nucleosynthesis of nitrogen is a vital component of the chemical evolution of galaxies in our universe. We estimate the nitrogen abundance and N/O ratio of dwarf galaxies using the direct T e method and spectroscopic line flux measurements from the SDSS DR7 sample as reprocessed in the MPA-JHU catalog. The 135 galaxies analyzed suggest a slight large-scale environmental dependence of the N/O ratio, where void dwarf galaxies could have a lower N/O ratio than dwarf galaxies in denser environments. Thus, the large-scale () environment might influence the chemical evolution of dwarf galaxies. We find small, statistically insignificant shifts in the mean (or median) N/O ratio for galaxies between the void and denser regions across all blue, star-forming galaxies with . These shifts are somewhat more significant, however, when we look at the entire sample of galaxies. Each magnitude bin is shifted in the same direction, and they are potentially very interesting, as they might indicate delayed star formation histories, more constant SFRs, and larger ratios of dark matter halo mass to stellar mass in void galaxies, as discussed in Section 5 . A larger sample would help test these results. We look to increase the sample and probe a larger magnitude (and mass) range of dwarf galaxies in K. A. Douglass M. S. Vogeley (2017, in preparation). In addition, we look at the relationship between the N/O ratio and other physical characteristics of our dwarf galaxies. In the relation between N/O and O/H, our galaxies all reside on the so-called “nitrogen plateau,” where the N/O ratio is predicted to be constant for low and intermediate metallicities. However, instead of a constant value for these galaxies, we find a negative correlation between the N/O and O/H ratios. Our dwarf galaxies show a positive correlation between stellar mass and the N/O ratio. These dwarf galaxies have some of the lowest N/O ratios for both their color and (s)SFR. Beyond the suggestive large-scale environmental dependence of the N/O ratio, there is no clear large-scale environmental dependence in any of these relationships. The N/O ratios of the extremely metal-poor dwarf galaxies are no different than those of the remaining dwarf galaxy sample, though their N/H abundance is also extremely low. A more detailed study of these 21 extremely metal-poor dwarf galaxies is recommended to confirm their abundance values and discover any characteristics shared by the population. Although SDSS provides