Exegesis:

meta … tauta ‘after this’: this temporal phrase is not used by Mark.

dusin ex autōn peripatousin … poreuomenois eis agron ‘to two of them as they were walking … going to the country’: this appearance would seem to be that one which is described in Lk. 24.13-35.

peripateō (cf. Mk. 2.9) ‘walk,’ ‘walk about.’

poreuomai (cf. v. 10) ‘go.’

eis agron (cf. ap’ agrou Mk. 15.21) ‘to the country’: the context implies a journey from Jerusalem out to the neighboring rural region.

ephanerōthē en hetera morphē ‘he was manifested in another form,’ ‘he appeared in a different fashion’: the statement seems to be that this appearance was in a form different from that in which he appeared to Mary.

phaneroō (not used with this meaning in Mark; cf. v. 14) ‘to make manifest’; in the passive, as here, ‘to be made manifest,’ ‘to appear’ (in Mk. 4.22 of a hidden matter, ‘to be revealed’). Translator’s New Testament translates here ‘He was revealed.’

en hetera morphē ‘in a different form’: what is meant, apparently, is that in manifesting himself to these two Jesus took on a different form or appearance from that in which he appeared to Mary. The adjective heteros ‘another,’ ‘different’ is not in Mark, nor is morphē ‘form,’ ‘shape,’ ‘appearance’ (elsewhere in the N.T. it appears only in Phil. 2.6, 7). In the Transfiguration story in Mark the change which Jesus underwent is described by Mark by the verb metamorphoō (Mk. 9.2).

Translation:

Appeared in another form may be rendered as ‘came to two of them in a different appearance’ or ‘he looked different as he came to two of them.’ In Tzeltal this is rendered as ‘looking like another.’

Into the country identifies the open country away from the city, roughly equivalent to ‘out into the fields’ in some languages.

Quoted with permission from Bratcher, Robert G. and Nida, Eugene A. A Handbook on the Gospel of Mark. (UBS Handbook Series). New York: UBS, 1961. For this and other handbooks for translators see here .