"As many members are aware the number of Post Offices open in 1891 is known and included the following seven T.P.O.s: Bartica Steamer, Berbice River Steamer, Demerara River Steamer, Essequibo Steamer, Mail Boat Demerara River and Massaruni Steamer. Since then others have, of course, been opened and a number no longer exists. I always like to record the earliest known postmarks for each T.P.O. which I have obtained in many instances from articles published in philatelic journals and, in other cases, from the cancellations on some of my friends' or my own stamps. Ignoring the enigmatic code mark E.R., my listing is as follows:
| Bartica Steamer | 1891? (10.4.01) | Essequibo Steamer 1881? | (29.10.83) | |
| Berbice Railway | 10.9.08 | Mail Boat Demerara River | 24.2.99 | |
| Berbice Steamer | 1884? (3.11.86) | Massaruni River | 24.8.96 | |
| Demerara Railway | 1.12.87 | Pomeroon | 7.9.00 | |
| Demerara River Steamer | 27.9.83 | Suddle Steamer | 7.?.00 | |
| East Coast Railway | 4.11.99 | West Coast Railway | 12.12.12 |
Note: The dates in parenthesis are those in my own collection.
I am anxious to ascertain how long each one of these services existed - at any rate with a postmark of its own - and shall he glad if any members can amend the listing. Incidentally I have yet to find a specimen of 'North West Str' (mentioned by Mr. Hosking in Bulletin No. 10. p. 31.) and Purini River."