The Bulldog and Bird classes were double-framed inside cylinder 4-4-0 steam locomotives used for passenger services on the Great Western Railway.

[1] The Bird Class were a development of the Bulldogs with strengthened outside frames, of which a total of fifteen were built.

A total of 121 Bulldogs were built new, with a further twenty rebuilt from Duke Class locomotives.

Thirty Bulldogs were later rebuilt as Earl Class locomotives and renumbered 3265 (prototype conversion), 3200-3228.

3312 Bulldog was built in October 1898, with curved outside frames, a domed parallel boiler with a raised Belpaire firebox and a wrapper-type smokebox.

2 boiler, domeless, with a raised Belpaire firebox and a circular drumhead smokebox supported on a curved saddle.

[5] Between May and December 1900 a second batch of twenty Camels (as the class were initially known) were built with straight-topped outside frames.

[8] A further twenty-nine locomotives were built with the half-cone boiler between September 1903 and April 1904, bringing the class total to ninety-one.

From October 1906 to January 1909 eighteen of the Duke Class were converted to Bulldogs by the fitting of No.

3273 Armorel, had been fitted with a parallel domeless boiler in February 1902, thus becoming a Camel Class locomotive.

All of the Bird Class survived into British Railways ownership, being withdrawn between April 1948 and November 1951, the last two being no.