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We have carried out survey observations of molecular emission lines fromHC$_{3}$N, N$_{2}$H$^{+}$, CCS, and cyclic-C$_{3}$H$_{2}$ in the 81$-$94 GHzband toward 17 high-mass starless cores (HMSCs) and 28 high-mass protostellarobjects (HMPOs) with the Nobeyama 45-m radio telescope. We have detectedN$_{2}$H$^{+}$ in all of the target sources except one and HC$_{3}$N in 14HMSCs and in 26 HMPOs. We investigate the $N$(N$_{2}$H$^{+}$)/$N$(HC$_{3}$N)column density ratio as a chemical evolutionary indicator of massive cores.Using the Kolmogorov-Smirnov (K-S) test and Welch's t test, we confirm that the$N$(N$_{2}$H$^{+}$)/$N$(HC$_{3}$N) ratio decreases from HMSCs to HMPOs. Thistendency in high-mass star-forming regions is opposite to that in low-massstar-forming regions. Furthermore, we found that the detection rates ofcarbon-chain species (HC$_{3}$N, HC$_{5}$N, and CCS) in HMPOs are differentfrom those in low-mass protostars. The detection rates of cyanopolyynes(HC$_{3}$N and HC$_{5}$N) are higher and that of CCS is lower in high-massprotostars, compared to low-mass protostars. We discuss a possibleinterpretation for these differences.

Survey Observations to Study Chemical Evolution from High-Mass Starless Cores to High-Mass Protostellar Objects II. HC$_{3}$N and N$_{2}$H$^{+}$