Percy Daniels' World War I draft registration card can be found at FamilySearch.org by using this link. (Find another name in the index using this link from my Links page).
For more information about Percy Daniels, see the Daniels page.
Percy Registered at the New York Public Library located at 31-33 East Broadway. These two images are from Google Maps, showing where he lived and where he registered.
I ♥ Google Maps and FamilySearch.org
"United States World War I Draft Registration Cards, 1917-1918," index and images, FamilySearch (https://familysearch.org/pal:/MM9.3.1/TH-1951-26581-5537-60?cc=1968530 : accessed 2 June 2015), New York > New York City no 91; A-G > image 3250 of 5725; citing NARA microfilm publication M1509 (Washington, D.C.: National Archives and Records Administration, n.d.).