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\section{Analysis of New Bones}  BC\_18.88-0.09 is our strongest bone candidate, in that it is highly elongated (0.7 degrees or 45 pc, with an aspect ratio of 140:1) and \textit{exactly} along a previously-claimed spiral arm trace in \textit{p-p-v} space, although its orientation makes it less somewhat elongated than Nessie on the sky. In figure \ref{fig:Candid5_pos_vel} we show a \textit{p-v} diagram in the longitude range of BC\_18.88-0.09 and overlay fits to the Scutum-Centaurus arm from \citet{Shane_1972}, \citet{Vallee_2008}, \citet{Dame_2011}, and Reid and Dame (2015), in prep. We see that the HOPS, BGPS, and GRS-determined velocities associated with BC\_18.88-0.09 are highly correlated with the \citet{Dame_2011} and Reid \& Dame (2015) global-log fits to CO and HI, suggesting that BC\_18.88-0.09 is marking a "spine" of the Scutum-Centaurus arm in this longitude range. Moreover, BC\_18.88-0.09 also lies along a CO peak in longitude-latitude space, as evident in figure \ref{fig:Candid5_pos_pos}. By overlaying a trace of the mid-IR extinction feature of BC\_18.88-0.09 on a plane of the sky map (integrated in Scutum-Centaurus's velocity range in the region around BC\_18.88-0.09) we see that BC\_18.88-0.09 lies in the center of the most intense CO emission. Finally, figure \ref{fig:Candid5_with_tilt} shows that BC\_18.88-0.09 lies within $\approx$ 10 pc of the true physical mid-plane. All these figures taken together indicate that BC\_18.88-0.09 is Nessie's counterpart in the first quadrant, suggesting that Nessie is not a curiosity, but one of several bones that trace significant spiral features.   Our study is not the first follow up to the Nessie work in \citet{Goodman_2014} to look for more long filaments associated with spiral structure. \citet{Ragan_2014} and Wang et al. (2015) have undertaken similar studies. However, ours is the first study to specifically look for bones in regions we are most likely to find them, that is, elongated along the galactic Galactic  plane. Moreover, ours is the only study to create a quantitative set of criteria capable of defining this new class of objects (i.e. galactic "bones"). In the former study, \citet{Ragan_2014} undertook a blind search (not ({\it not}  restricted to latitudes where the mid-plane should lie) for long thin filaments (> $1^\circ$) in the first quadrant of the Milky Way, using near and mid-infrared images. In addition to confirming that Nessie lies along the Scutum arm, \citet{Ragan_2014} find seven GMFs of which only one, GMF 20.0-17.9, is said to be associated with Galactic structure (declared a spur of the Scutum-Centaurus arm). Our strongest bone candidate, BC\_18.88-0.09, is a subsection of GMF 20.0-17.9, but, unlike \citet{Ragan_2014}, we argue that BC\_18.88-0.09 runs right down the spine of the Scutum-Centaurus arm in \texit{p-v} space. We believe the discrepancy arises due to a difference in methodology. \citet{Ragan_2014} group neighboring IRDCs into a single filament, despite a) breaks in the extinction feature and b) kinks in velocity structure. Since grouping several IRDCs to make a longer structure violates our criteria 1 and 6, we only consider the continuous and kinematically coherent part of the filament, which is remarkably parallel to the Scutum-Centaurus arm in \textit{p-v} space. Likewise, in figure 4 from \citet{Ragan_2014} (analogous to our figure \ref{fig:skeleton}), they represent filaments as straight lines connecting velocities measured at the tips of the filaments while we represent filaments as sets of points whose velocities are determined by the BGPS, HOPS, MALT90, and GRS surveys. We compare our p-p and \textit{p-v} analysis of BC\_18.88-0.08 with the analysis from \citet{Ragan_2014} in figure \ref{fig:ragan_comp}. Since \citet{Ragan_2014} find little or no association with their filaments and Galactic structure, they speculate that perhaps we are not as sensitive to spiral arm filaments in the first quadrant, or that the frequency and orientation of spiral arm filaments in the first quadrant is different than the fourth. Since three of our strongest bone candidates (BC\_18.88-0.09, BC\_26.94-0.30, BC\_25.24-0.45) all lie in the first quadrant, we argue against the above speculations. Once again, we attribute the discrepancy not to a difference in frequency or sensitivity, but to a difference in methodology. Unlike \citet{Ragan_2014}, we never used minimum angular length as a criterion because no bone is likely to be as long as Nessie, given its extremely favorable position on the sky. As a result, we argue that bones are not necessarily the longest features on the sky, but the longest features that have incredibly high (>50:1) aspect ratios when compared to the typical Giant Molecular Cloud. Since parts of GMFs from \citet{Ragan_2014} are too diffuse to allow for the measurement of their widths, no complete GMF from that study could reasonably meet our bone definition. Thus, a clear and consistent description of a bone is critical, and, in future studies, we plan to continue to apply the criteria above to achieve consistency.