Collylin Road was built around 1895 – it is not mentioned in the New Kilpatrick Valuation Roll of 1895 but appears on a map surveyed in 1896:

It’s interesting to compare this to the 1949 map, the first I know of with street numbers (sorry number 20, your property is just ff the map!):

Numbers 10-12 seem to have been built on what was originally a vacant plot, possibly laid out as a garden
Directly opposite this, the site of the future number 15 is also vacant
On the south side the main gap is between 5 and 9. While there is a number 7 it appears to be a building within 10 Ledcameroch Road (a gardener’s cottage?)
Number 1 – unclear whether this was previously numbered in Drymen Road
Number 3 was called Craigour 1915-1920. In 1922 it was the original site of Drewsteignton School, which moved to Glenburn Road in 1924 and ultimately merged with the High School of Glasgow. From 1925 to 1940 it was called The Linn.
Owner: Robina Robertson (1905-1915). Occupier: Alexander Stevenson (1915), Spencer Ponsford (1920), Shepherd (1925 and 1930), Pagan (1935), Ballantine (1940)
Number 5 was called Austin Villa in 1905 and then Strathearn (1915-1940).
Owners: James B R Morton (1905), then David Stenhouse (1915-1940)
Number 7 – as can be seen from the 1949 map, this appears to be a property at the rear of 10 Ledcameroch Road.
Number 9 was called Rosslyn between 1905 and 1935 and appears as Cairngillan in 1940.
Owner: Matthew White (1905-1915). Occupiers: Adam B Keay (1915-1930), Steven (1935 and 1940)
Number 11 was called the same name throughout the period but the spelling changed from Aldowrie to Aldourie.
Owner: Gustav Theodore Gerstenberg (1905 to 1940)
Number 13 – there is no number 13.
Number 15 was called Kirnan throughout the period 1905-1940.
Owner: Reverend John C Gibson (1905-1920), Stuart (1921), Carson (1925 to 19400
Number 17 was called Glencairn 1905-1930 and Dreva from 1935-1940.
Owner: George J Thompson (1905), Kate McLelland (1915 to 1930), Agnew (1935), Templeton (1940)
Number 19 was called Borlum throughout the period 1905-1940
Owner: Marjory Helen Ramsay or Gordon (1905-1915), Gordon (1920-1940)
Number 21 was known as Kincraig throughout the period 1905-1940.
Occupier: Mary Paterson (1905-1925), Thomas William Dalgleish (1930 to 1940)
Number 20 was known as Coniston in 1905 and then as Balintore (1915 to 1940)
Owner: Margaret Coubrough (1905, occupier Andrew Forsyth), John Smart (1915-1920), McQuistan (1925 to 1940)
Number 18 was known as Nithsdale (1905-1925) and Stamford (1930 to 1940)
Owners: Margaret K Inglis (1905-1920), Reid in 1921, Hawkins in 1925, Billing (1930 to 1940)
James Milne Monro Billing, son of the owner, is named on the War Memorial at Bearsden Cross
Number 16 was known as Woodmyre (1905 to 1935) and Kendoon (1940)
Owners: William Gowans (1905-1935) and Abell (1940)
Number 14 was known as Gordon Villa (1905-1915), then Hermiston (1920 to 1940)
Owners: Robert Howie (1905-1915, occupier Jessie Howie), Hutchison (1920-1925), MacLean (1930), Mann (1935), Begg (1940)
Number 12 was known as Glenartney (1905-1930) and then Ronbank (1935-1940)
Owner: Archibald Orr (1905-1930), MacLachlan (1935-1940)
Number 10 was known as Balcardine (1905-1940)
Owner: James MacMillan (1905), then Jessie Pollock (1915, occupier Galloway). Then Janet Forrest Pollock (1920), Walter Clarke (1925-1940)
Number 8 was the Manse for the North Church on the corner of Thorn Road and Drymen Road. In 1905 the house was called The Hewan.
Occupier: Rev James Peattie (1905), Rev Hugh Watt (1915), Rev Paterson (1920-1930), Rev MacLennan (1935-1940)
Number 6 was known as Fernlea throughout the period 1905 to 1940
Owner: John Stoddart Robertson (1905, 1915). Occupiers: Miss Margaret Rodger (1905-1920), Merton (1921, 1925), Lindsay (1930), Ausitn (1935-1940)
Number 4 was known as Heath Villa (possibly Heathville as well) throughout the period 1905 to 1940.
Owner: John Stoddart Robertson. Occupier: Edward E MacDonald (1905), William Hunter MacFarlane (1915-1940)
In World War One, the second son of Edward Macdonald was killed and is named on the war memorial at Bearsden Cross.
Number 2 was named Hazeldene (1905-1925), then Benverren (or Ben Varren)
Owner: James Milne Monro (1905-1915). Occupier Harry Taylor (1905), Charles Monro (1920-1930)
An aerial photo from the Britain from Above, dated 1928 looking at Collylin Road from the south. First, the Drymen Road end:

Second, the Whitehill Road end:

This 1955 photo is from a similar direction:

Unfortunately, the damage to the photo on the left hand side is present in the original.