Gizzard -> Crop ->?Malphigian tubules ->?Hepatic caeca ->?Rectum.
Gizzard -> Hepatic caeca -> Crop -> Rectum -> Malphigian tubules.
Crop -> Gizzard ->?Hepatic caeca ->?Malphigian tubules ->?Rectum.
Crop -> Hepatic caeca ->?Gizzard -> Rectum -> Malphigian tubules.