If it is true that a stone was stolen from the site (as is stated on the sign-post and by Harbison), and if it was an inscribed one, it can only have been this one, read as UMALL by Macalister. It seems probable, however, that the present stone, no. {208} in Macalister's CIIC, never existed as such, the record having emerged from a confusion with the stone numbered {213} in Macalister's own data only. There are several arguments in favour of this hypothesis:
a) Older records (Brash, Ferguson) know only the fragment read by them as URG; this is no. {213} in the CIIC;
b) In Epig. 2, 101, Macalister mentioned only a fragment read by him as DDAMU; he wondered whether this might be the fragment read as URG and RRI by Brash and Graves, resp.: "If this be really the stone seen by them I cannot follow either reading". This means at least that Macalister never saw a fragment readable as URG himself.
c) In CIIC, Macalister lists the fragment reading UMALL and another fragment reading URG side by side as nos. {208} and {213}, resp. There is only one drawing included, however, viz. the one of {213} readable as URG. In Epig., however, the only drawing included shows what might be read as UMALL, i.e. {208}.
d) In CIIC, a size is given for {213}, not for {208}.
e) Both readings, URG and UMALL, are not so different that they might not conceal the same inscription: cp. äòñð and äïâèè
f) Harbison, Guide 115 speaks of "six Ogham stones" at Kilcoolaght, plus a stolen one. He lists the one reading UMALL, but not the one reading URG (but there are "two indecipherable inscriptions" according to him).
g) According to J. Rhßs, JRSAI 16, 1884, 314, there were seven stones at the site at his time (and he warned that they could easily be "removed"). But even if nos. {208} and {213} are actually one stone, we are left with seven still today.
This is why both stones are be dealt with jointly here. Cf. Gippert, Pr„liminarien for a more detailed discussion of the problems involved.

Size according to Brash, OIM 230: 12" x 4" x 8".
Size according to Macalister, CIIC {213}: 1' x 4" x 3"

Published illustrations:

Brash, OIM, pl. XXXI, no. 3. (draft);

Macalister, Epig. 2, 101 (outline of the inscription);

Macalister, CIIC, 205 {213} (sketch of the inscription only).

Reading Brash, OIM 230 (3.):