The o’-lag is the dormitory of the girls in an a’-to from the age of about 2 years until they marry.  It is a small stone and mud-walled structure, roofed with grass, in which a grown person can seldom stand erect.  It has but a single opening —­ a door some 30 inches high and 10 inches wide.  Occupying nearly all the floor space are boards about 4 feet long and from 8 to 14 inches wide; each board is a girl’s bed.  They are placed close together, side by side, laid on a frame about a foot above the earth.  One end, where the head rests, is slightly higher that the other, while in most o’-lag a pole for a foot rest runs along the foot of the beds a few inches from them.  The building as shown in Pl.  XXXIII is typical of the nineteen found in Bontoc pueblo —­ though it does not show, what is almost invariably true, that it is built over one or more pigsties.  This condition is illustrated in Pl.  XXIX, where a widow’s house is shown literally resting above the stone walls of several sties.  Unlike the fawi and pabafunan, the o’-lag has no adjoining court, and no shady surroundings.  It is built to house the occupants only at night.

The o’-lag is not so distinctly an ato institution as the pabafunan and fawi.  Ato Ungkan never had an o’-lag.  The demand is not so urgent as that of some ato, since there are only thirteen families in Ungkan.  The girls occupy o’-lag of neighboring ato.

The o’-lag of Luwakan, of Lowingan, and of Sipaat (the last situated in Lowingan) are broken down and unused at present.  There are no marriageable girls in any of these three ato now, and the small girls occupy near-by o’-lag.  These three o’-lag will be rebuilt when the girls are large enough to cook food for the men who build.  The o’-lag of Amkawa is in Buyayyeng near the o’-lag of the latter; it is there by choice of the occupants.

Mageo, with her twenty families, also has two o’-lag, but both are situated in Pudpudchog.

The o’-lag is the only Igorot building which has received a specific name, all others bear simply the class name.[12]

In Sagada and some nearby pueblos, as Takong and Agawa, the o’-lag is said to he called If-gan’.

Mr. S. H. Damant is quoted from the Calcutta Review (vol. 61, p. 93) as saying that among the Nagas, frontier tribes of northeast India —­

Only very young children live entirely with their parents; ... the women have also a house of their own called the “dekhi chang,” where the unmarried girls are supposed to live.

Again Mr. Damant wrote: 

I saw Dekhi chang here for the first time.  All the unmarried girls sleep there at night, but it is deserted in the day.  It is not much different from any ordinary house.[13]

Separate sleeping houses for girls similar to the o’-lag, I judge, are also found occasionally in Assam.[14]

Whereas, so far as known, the o’-lag occurs with the Igorot only among the Bontoc culture group, yet the above quotations and references point to a similar institution among distant people —­ among some of the same people who have an institution very similar to the pabafunan and fawi.