For administrative purposes the natives were classed in three social divisions--_Indios_, _Infieles_, and _Moros_--which, as aptly remarked by F. H. H. Guillemard, is "an ecclesiastical rather than a scientific classification[554]." The _Indios_ were the Christianized and more or less cultured populations of all the towns and of the settled agricultural districts, speaking a distinct Malayo-Polynesian language of much more archaic type than the standard Malay. According to the census of 1903 the total population of the islands was 7,635,428, of whom nearly 7,000,000 were classed as civilised, and the rest as wild, including 23,000 Negritoes (_Aeta_, see p. 156). At the time of the Spanish occupation in the sixteenth century the _Visayas_ of the central islands and part of Mindanao were the most advanced among the native tribes, but this distinction is now claimed for the _Tagalogs_, who form the bulk of the population in Manila and other parts of Luzon, and also in Mindanao, and whose language is gradually displacing other dialects throughout the archipelago. Other civilised tribes are the _Ilocano_, _Bicol_, _Pangasinan_, _Pampangan_ and _Cagayan_, all of Luzon. Less civilised tribes are the _Manobo_, _Mandaya_, _Subano_ and _Bagobo_ of Mindanao, the _Bukidnon_ of Mindanao and the central islands, the _Tagbanua_ and _Batak_ of Palawan, and the _Igorots_ of Luzon, some of whom are industrious farmers, while among others, head-hunting is still prevalent. These have been described by A. E. Jenks in a monograph[555]. The head form is very variable. Of 32 men measured by Jenks the extremes of cephalic index were 91.48 and 67.48. The stature is always low, averaging 1.62 m. (5 ft. 4 in.) but with an appearance of greater height. The hair is black, straight, lank, coarse and abundant but "I doubt whether to-day an entire tribe of perfectly straight-haired primitive Malayan people exists in the archipelago[556]." Under _Moros_ ("Moors") are comprised the Muhammadans exclusively, some of whom are Malayans (chiefly in Mindanao, Basilan, and Palawan), some true Malays (chiefly in the Sulu archipelago). Many of these are still independent, and not a few, if not actually wild, are certainly but little removed from the savage state. Yet, like the Sumatran Battas, they possess a knowledge of letters, the Sulu people using the Arabic script, as do all the Orang-Malayu, while the Palawan natives employ a variant of the Devanagari prototype derived directly from the Javanese, as above explained. They number nearly 280,000, of whom more than one half are in Mindanao, and they form the bulk of the population in some of the islands of the Sulu archipelago.