The U.S. Special Delivery Postage Stamps · 1885-1971

Number E1
10¢ Running Messenger
No Dashes under "OFFICE"
Issued: 10/1/1885
EDU: 9/29/1885
Number E2
10¢ Dashes under "POST OFFICE"
Issued: 9/6/1888
EDU: Oct. 5, 1888
Number E3
Orange 10¢ Running Messenger
Issued: 1/24/1893
EDU: 2/1/1893
Number E4
10¢ Messenger
Line Under "CENTS"
No Wmk
Issued: 10/10/1894
EDU: 10/25/1894
Number E5
10¢ Double-line Watermark USPS
Issued: 8/16/1895
EDU: 10/3/1895
Number E6
10¢ Bicycle Messenger
perf 12  D/L Wmk
Issued: 12/9/1902
EDU: 1/15/1903
Number E7
10¢ Helmet of Mercury
Issue: 12/12/1908
EDU: 12/14/1908
Number E8
10¢ Single-line Watermark  Perf 12
Issued: 1/14/1911
EDU: 1/?/1911
Number E9
10¢ Messenger on Bicycle
Perf 10 S/L Wmk
Issued: Sep. 1914
EDU: 10/26/1914
Number E10
10¢ Unwatermarked
Perf 10
Issued: 10/10/1916
EDU: 10/24/1916
Number E11
10¢ Messenger on Bicycle
Perf 11
Issued: 5/2/1917
EDU: 6/12/1917
Number E12
10¢ Gray violet
Motorcycle Messenger
Issued/FDC: 7/12/1922
Number E13
15¢ Deep Orange Motorcycle Messenger
Flat Plate Printing
First Day: April 11, 1925
Number E14
20¢ Messenger by Truck
Flat Plate Printing
First Day: April 25, 1925
Number E15
10¢ Motorcycle
Rotary Press
First Day: November 29, 1927
Number E16
15¢ Motorcycle
Rotary Press
Issued: 8/13/1931
EDU: 8/6/1931
Number E1
16¢ Great Seal
Air Mail Special Delivery
First Day: August 31, 1934
Number CE2
16¢ Great Seal
Air Mail Special Delivery
First Day: February 10, 1936
Number E17
13¢ Motorcycle Delivery
Rotary Press
First Day: October 30, 1944
Number E18
17¢ Orange Yellow Motorcycle Delivery
Rotary Press
First Day: October 30, 1944
Number E19
20¢ Truck Messenger
Rotary Press Printing
First Day: Nov 30, 1951
Number E20
20¢ Carrier Delivering Letter
First Day: October 13, 1954
Number E21
30¢ Carrier Delivering Letter
First Day: September 3, 1957
Number E22
45¢ Arrows
First Day: November 21, 1969
Number E23
60¢ Arrows
First Day: May 10, 1971

Bibliography and suggested additional reading:

Basic Information:
A special thank you to Bob Markovits for providing edu dates for the special delivery stamps.
The Speedy: A History of the United States Special Delivery Service, by Henry M. Gobie (1976)
The First Bureau Special Delivery Service, by Robert L. Markovits (28th American Philatelic Congress 1962)
The Rise and Fall of the Merry Widow, a Comprehensive Study of Number's E7, by Robert L. Markovits (41st American Philatelic Congress - 1975)