A call like 'glance show e6421c88- b1ed-4407- 8824-b572982490 91' will return the following output:

URI: http:// h:t/v1/images/ e6421c88- b1ed-4407- 8824-b572982490 91
Id: e6421c88- b1ed-4407- 8824-b572982490 91
Public: Yes
Protected: Yes
Name: cirros- 0.3.0-x86_ 64-uec- kernel
Status: active
Size: 4731440
Disk format: aki
Container format: aki
Minimum Ram Required (MB): 0
Minimum Disk Required (GB): 0
Owner: 2b74d1ddbccc40c 99234b1fdb290f1 18
Created at: 2012-08-10T19:23:49
Updated at: 2012-08-10T19:23:49

Notice the 'URI: ...' field shows 'h' and 't' for the host and port. That field should be a valid hostname that the image can be reached at.