N.B. THIS STONE IS NOW IN THE McMANUS GALLERIES, DUNDEE.

When this stone was recorded by Allen and Anderson in their ECMS, it was still embedded in the wall of the Church at Tealing at Gallow Hill. It was in the South wall about 18ft (550 cms) from groundlevel and only the cross side was showing.
Apparently, the stone was removed from the wall, and lay in the churchyard for some time, until it was handed over to Dundee Museum on a long-term loan. The present church was built in 1806, but is now disused. In the churchyard, there are gravestones going back to the 1600s, and during repairs to a steading in what used to be the old manse, a monographed stone dated 1656 fell out of the wall. The initials matched a graveslab of the same period in the graveyard. The manse has dozens of old dressed stones built into its walls, so it looks like there was a substantial old building nearby, if not actually on the site of the converted farmhouse that was the manse.
Since the walls of the current church is rendered, it is impossible to say what the fabric below is like.

There are records of a church at Tealing from the 13th Century, but the presence of the cross-slab may indicate there was a religious site before that. Martin's Stone is literally a couple of miles West of it, with the Strathmartine clutch of stones and fragments found close bye.
Between the Kirkton of Tealing and St Martin's Stone, there is a small stone circle (about 1½ miles West) and just 1 mile beyond Martin's Stone, a large standing stone that isn't marked on the OS Maps, at Old Balkello. Just 1½ miles ( 2.5kms) beyond that, still going westerly there is Kirkton of Auchterhouse. There is is a hillfort on Auchterhouse, and four souterrains at Tealing, which indicates a long period of settlement in the area.
Also about 1½ miles easterly above Tealing on Tealing Hill, there are standing stones.
I remember seeing a map that showed a rectangular section in the Parish Boundary opposite St Martin's Stone, and it made me wonder if it indicated a chapel or somesuch. There was also an abandoned church on the same road as the stones above Tealing. I can't recall where I saw it. It was long long ago... I only mention them, in case it means something to someone else. I'll chase the references up sometime, if no-one else does before then.
Across the road, further up Gallows Hill, on which Kirkton of Tealing is deemed to lie, although it is all one long sloping rise to the ridges of the Sidlaws, lies Prieston and Hillhead of Prieston, which possibly refers back to to some ecclesiastical grant of land i.e. Priest-ton, the Priest's Farm or Hamlet.
Kirkton of Tealing refers to the Ton, Toun or Town that went with the Kirk or Church in medieval times, to help provide a living for the priest or minister who held the post. A preacher would be granted land from a landowner, and possibly bondsmen ( a polite word for slaves) to work his land, plus income in cash or kind from his parishioners. Out of that he would pay for the keep of his manse and his kirk, and forward some of it to the Bishop of his Diocese.
There are many "Kirktons" scattered all over the country, and the name survives, even though the kirk doesn't.
"Towns" as we know them nowadays were extremely rare in this part of the world, and a "toun" might be no more than a large farm with tenants and subtenants clustered around it. Weavers and woodsmen etc might attach themselves to a farm for protection, if they did not form a "toun" of their own. In short, touns might easily be as few as two or three dozen souls huddled together instead of being scattered on individual crofts.

When writers refer to Tealing in older books, they most likely mean Kirkton of Tealing, because what is now "Tealing" was previously "Balgray" on older maps. When I lived in Dundee, we knew the place as Tealing, and I note the maps reflect this common usage.

The Stone.

The stone is obviously about a quarter of the original slab, ending as it does below the RH arm of the cross, and having a section of the shaft as its LH side. The shape of the remnant makes me think it might have been broken up for lintels, unless it is a pure fluke that any design at all survived. The stone must have been about 2ft 6ins wide by about 4ft tall in total, with the cross occupying approximately 3ft 4ins of that, assuming the arms were equal-sized. (75cms wide x 140 cms tall x 17cm thick)
The surviving section of cross shows a shaft with a notch at the junction between it and the arm, and the shaft ends in an unusual angled foot #####, instead of the usual "box" #####.
The space between the shaft and the edge of the stone is occupied by an amazing seahorse-like beast with a fascinating head. The eyes are huge and staring, and it has huge flared nostrils (See detail )
This creature overlies a snake of some kind, which is plain, while the beast is carefully carved and decorated with what looks like an unfinished knotwork pattern. It starts out looking like knotwork at the tail, but becomes a zig-zag one-third of the way up the body as if the basic lines had been inscribed, and the carving hadn't been finished for some reason. Did some catastrophe befall the stone before it was completed ?
The other sideof the stone has even less carving visible on it, as the way the stone has sheared cuts the Dolphin in half just behind the shoulders. All that survives is the head with the beginning of the curlicue, and a rather inelegant snout. Thee is also the front leg/ flipper with the familiar curled ending.
There is a border of Greek key pattern, with a skewed version of it inside.
It is a pity so much of the stone is missing, given that the "seahorse" is so interesting. Who knows what other bizarre things the sculptors might have created?