The former parish is now part of St Michael and All Angels with St James which has an official website at http://www.croydonstmichael.org.uk/. This includes a more detailed history of St James's.
<More photos>
St James's Church, which was made redundant and has been converted into flats, lies on the south-west side of the junction of St James's Road and Sydenham Road. This, of course, is outside Addiscombe itself but the parish would have covered the Davidson Road and Morland Road area before the formation of St Martin's.
I don't know how the parish boundaries ended up. The parish merged with St Michael's in 1980 and that parish wasn't huge to start with.
<Parish boundary map of St Michael's>
Building of St James's Chapel, on Croydon Common, began on 16th May 1827 to the designs of Robert Wallace and it was consecrated on 30th January 1829. The Chapel became the Parish Church of Saint James's Croydon Common on 11th March 1853.
One description of Croydon Common has it roughly bordered by North End, London Road, Windmill Road, Selhurst Road, Cherry Orchard Road and George Street. This seems to me to be a little vague on the eastern side (there was no railway back then, but there was the Croydon Canal on pretty much the same alignment) and perhaps a little too confined on the north-western side.
Holy Trinity on the Selhurst Road (just up from the Selhurst Arms and now demolished) was formed out of the parish in 1867 and St Saviour's (now Holy Saviour and dated as 1869 in other sources) was created as an ecclesiatical district. In 1871 part of the parish went to create the ecclesiastical district of St Michael and All Angels.
The parish boundary of Holy Saviour is a little curious on the east side, as is that of St Alban The Martyr in South Norwood on the south-east side, which suggests that the parish of Holy Trinity might have been shared between them when the church closed.
Work began on enlarging the church to the designs of Charles Henman Jnr in 1873 and the additions were consecrated on the 20th December 1880. A new reredos was added in 1884.
In 1902 St Martin's opened as a chapel-at-ease covering the Davidson Road and Morland Road area. It became a parish in 1927 and merged with St Mary Magdalene in 1994 when the church was demolished.
The Victoria County History of Surrey written in 1912, says of the church:
"The church of ST. JAMES, Croydon Common, was built in 1827–9, and a parish was formed for it in 1853. It originally consisted of the present nave and west tower with a small chancel recess at the east end. The materials of this portion of the building are stock brick with stone dressings, and the style is best described as 'pointed.' The roof is slated. The 'decorated' chancel, with its vestries, organ chamber and south chapel, was added in 1881. The walls are faced with Kentish rag and the roofs are tiled."
The Church held its last service on 27th January 1980 and the parish merged with St Michael and All Angels.
In 1885 the church was purchased by the Croydon Churches Housing Association and converted into homes for the elderly. The completed scheme is known as Speaker's Court to commemorate Baron Bernard Weatherill of North East Croydon, a former Speaker of the House of Commons. The graveyard was cleared and landscaped by the council and forms an open space called St James's Memorial Garden.