cannot connect -- curl cannot resolve host name

[vjcitn]

graph = startGraph("http://localhost:7474/db/data/", username="neo4j", password="xxxx")
Error in curl::curl_fetch_memory(url, handle = handle) :
Couldn't resolve host name

browser session is fine, using neo4j community edition 3.1.3, R sessionInfo:

sessionInfo()
R Under development (unstable) (2017-03-02 r72298)
Platform: x86_64-apple-darwin13.4.0 (64-bit)
Running under: macOS Sierra 10.12.4

Matrix products: default
BLAS: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRblas.0.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.4/Resources/lib/libRlapack.dylib

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] RNeo4j_1.6.4 rmarkdown_1.4

loaded via a namespace (and not attached):
[1] httr_1.2.1 compiler_3.4.0 backports_1.0.5 R6_2.2.0
[5] magrittr_1.5 rprojroot_1.2 tools_3.4.0 htmltools_0.3.5
[9] curl_2.4 Rcpp_0.12.9 stringi_1.1.2 knitr_1.15.1
[13] stringr_1.1.0 digest_0.6.12 evaluate_0.10