Ref# 3
http://en.wikipedia.org/wiki/Purushamedha
The ritual in many aspects resembles that of the Ashvamedha (horse sacrifice), with, according to Griffith (1899)
man, the noblest victim, being actually or symbolically sacrificed instead of the Horse, and men and women of various tribes, figures, complexions, characters, and professions being attached to the sacrificial stakes in place of the tame and wild animals enumerated in Book XXIV [VS 24].
These nominal victims were afterwards released uninjured, and, so far as the text of the White Yajurveda goes, the whole ceremony was merely emblematical
.
The ceremony evokes the mythical sacrifice of Purusha, the "Cosmic Man", and the officiating Brahman recites the Purusha sukta (RV 10.90 = AVS 5.19.6 = VS 31.1–16).
Regarding the missing verses i am getting the original in sanskrit and will post once they are available.