^Remember the A. Marche findings in Marinduque (I posted it in archaeology thread), there was a debate about the skulls he found (his was the very first archaeological project anywhere in the Philippines).
Here's a blog post on it...I wouldn't trust it though unless you (or I) find better sources.
http://marinduquegov.blogspot.com/20...-ancestry.html
"In the 1860s public attention was aroused in the West with the discovery in Marinduque caves of deformed skulls. Up to that time nothing was known of such skulls in the oriental island world. These were gathered by anthropologist F. Jagor. There were similar finds during those years in the island of Cagraray at the entrance of the Bay of Albay.
It was believed that the natives of these islands practiced the custom of compressing the head of a newborn child between two boards so that instead of looking round it would be lengthened out with the forehead also flattened. This was considered as an ancient “special mark of beauty”.
Believed to have been buried in these caves long before the introduction of Christianity in the Philippines, they have been compared with similar crania from other parts of the South Pacific such as Chatham and Sandwich Islands then peopled by proto-Malays.
Marinduque’s fame for its funeral grottos, their legends, spirits and terrors, would eventually attract other anthropologists and archaeologists."
The whole rumors of 'deformed skulls' came from Marche's journal (which I posted again on the Archaeology thread and will link it here):
http://www.ulongbeach.com/marche.html
"When one enters their cavern, one sees nothing except skulls bigger than pots."
"Like the skulls found in the island of Los Tres Reyes, those of the cave of Pamin-Taan were deformed. I had brought about 40, most of which had their lower jaw and a dozen skeletons more or less complete."
"This visit, while not as fruitful as the preceding days, nevertheless gave me five deformed skulls. I also found the debris of many pots, sometimes broken by the natives who thought them full of gold."
Most likely it was miscommunication; most likely Marche meant skulls were 'almost destroyed' (as he said most of the skulls were deteriorated by humidity) and or that they were missing bits and pieces (he was trying to prove that the caves were used as secondary and not initial burial place, meaning they bury dead in the ground then gather bones and put them in coffins or vases before leaving them in caves, his proof was that teeth and jaw and craniums were found separated, with many times skulls were filled with 'dirt'---meaning it was dug up).
So whether it's reality or not, IDK, I think it has become folk myth in Marinduque more than anything. No proof of actual 'elongating skulls' are scientific.
However here is the commentary of Fedor Jagor (The Former Philippines in the Eyes of a Foreigner)
http://www.authorama.com/former-philippines-1.html
"[Study of a giant skull.] The cave in question lies near Lanang, on the east coast of Samar, on the bank of a river, it is said. It is, as the traveler reports, celebrated in the locality “on account of its depressed gigantic crania, without sutures.” The singular statement is made clear by means of a well-preserved example, which I lay before you. The entire cranium, including the face, is covered with a thick layer of sinter, which gives it the appearance of belonging to the class of skulls with Leontiasis ossea. It is, in fact, of good size, but through the incrustation it is increased to gigantic proportions. It is true, likewise, that it has a much flattened, broad and compressed form. The cleaning of another skull has shown that artificial deformation has taken place, which obviously was completed before the incrustation was laid on by the mineral water of the cave. I will here add that on the testimony of travelers no Negritos were on Samar. The island lies in the neighborhood of the Bisayas. Although no description of the position of the skull is at hand and of the skeleton to which it apparently belonged, it must be assumed that the dead man was not laid away in a coffin, but placed on the ground; that, in fact, he belonged to an earlier “period.” How long ago that was can not be known, unfortunately, since no data are at hand; however, the bones are in a nearly fossilized condition, which allows the conclusion that they were deposited long ago."
"I have sawed one of these skulls in two along the sagittal suture. The illustration gives a good idea of the amount of compression and of the violence which this skull endured when quite young. The cranial cavity is inclined backward and lengthened, and curves out above, while the occiput is pressed downward and the region of the front fontanelle is correspondingly lacking. Likewise, a considerable thickness of the bone is to be noted, especially of the vertex. The upper jaw is slightly prognathous and the roof of the mouth unusually arched."
"Since then the number of localities has multiplied. I shall mention only two, on account of their peculiar locality. One is Cagraray, a small island east of Luzon, in the Pacific Ocean, at the entrance of the Bay of Albay; the other, the island of Marinduque, in the west, between Luzon and Mindoro. From the last-named island I saw, ten years ago, the first picture of one in a photograph album accidentally placed in my hands. Since then I had opportunity to examine the Schadenberg collection of crania, lately come into the possession of the Reichsmuseum, in Leyden, and to my great delight discovered in it a series of skulls which are compressed in exactly the same fashion as those of Lanang. It is said that these will soon be described in a publication."
http://www.authorama.com/former-philippines-b-7.html
Since all of these are all prior to 1900's, I'd take them with a grain of salt.