During the long process of writing my book on Patagonian "Monsters", I read many papers, articles and books (especially books) written by explorers, missionaries and scientists who visited Patagonia between the 1500s and the early 1900s. In one of those books, I came across the image shown below, with the Spanish caption: "Ensayo de escultura, fueguino (on-asciaga) de Tierra del Fuego", which can be translated as: "attempt at a sculpture; Fueguian (on-asicaga) Tierra del Fuego" :
The image was published in a book that described the scientific expedition undertaken by the Italian captain Giacomo Bove, sponsored by the Argentine government, in 1881-1882. His was an expedition to Southern Patagonia, the Beagle Channel and Tierra del Fuego.
"On-asciaga" is the native Yaghan (also known as Yamana) name for the Beagle Channel . This Channel lies on the southern shores of the Isla Grande de Tierra del Fuego Island, and marks the border between Argentina (north) and Chile (south). By the way, in 1978, both countries almost went to war over three islands located on the eastern mouth of the Channel (Picton, Lennox and Nueva). War was averted and the dispute was settled peacefully (the islands are now Chilean).
These Yaghans (also known as Yamanas) were "canoe people" who moved about in their bark canoes (yes, they were made out of the bark of the Southern Beeches -Nothofagus sp. trees). They lived a nomadic life in the Fuegian channels and islands. They spent some time on land, in simple huts made from branches, and hunted the local seals or ate the mussels and crabs that were abundant in the Fuegian coastal waters.
The Yaghans were actually the southernmost people in the whole world.
Their closest neighbors were the Alakaluf (or Kawesqar) who lived in the islands of southwestern Patagonia to the north and west of the Yaghans. Both had a similar lifestyle differing only in their languages, they were usually fighting each other.
On the Isla Grande's mainland, there were two other groups of natives, one in the southeastern forests were the Haush (or Haus) the others lived in the grasslands of the North (the Selk'nam or Ona).
I was surprised because neither the Bridges (Thomas or Lucas), [*] who were the first Europeans to live in the region as from 1870, nor any other later (or earlier) explorer mentioned any Yamaná sculptures! or any artistic production beyond their tools or some body painting and ceremonial masks. 
[*] Thomas Bridges, (1842–1898). English Anglican minister who from 1869 until he retired in 1887 headed the mission among the Yagans, founding what is now the
town of Ushuaia. He later obtained a land grant from the Argentine government close to the town, and set up his estancia (sheep ranch) at Harberton. He also wrote
a very complete Yagan language dictionary.
Stephen Lucas Bridges, (1874-1949) was the third son of English Anglican missionary Thomas Bridges. Lucas was the first European to be born in Tierra del Fuego. He grew up among the Yagans and learnt their language and customs. He moved from Ushuaia to Harberton in 1887, where his father established a ranch ("estancia") after retiring from mission work. In 1902 he set up his own ranch at Viamonte, where he would meet and befriend the Selk'nam. His autobiographic book Uttermost Part of the Earth (1948) is a valuable source on Fuegian anthropology.
The Yaghan Mask
The Yamana used bark masks in their ceremonies (they are often refered to as hílix, but that is their word for quiver -to hold arrows, not for "mask"), some images are shown below  (see Another photograph):
The neighboring Kawésqar (or Alacaluf) canoe people used masks :
The image above is a photograph by Martin Guisinde (1923), showing a phallic "Yinchiahua" mask used during the male puberty initiation ceremonies.
The Fuegian native ceremonies invoked evil spirits and the men got dressed up to represent them. The best known is the Selk'nam's "Hain" ceremony, which was witnessed by Europeans in the late 1800s (Lucas Bridges). The Yaghans also had a similar rite, "Chiejaus" which was studied much later in the 1920s, when they had lost nearly all of their ancient customs and had already been absorbed into Western "civilization".
Fuegian males -of all groups- had a fixation with women’s freedom and they went to extremes to subjugate them. Their myths indicate that in the past men were under female domination until they revolted and adopted initiation rites in which they donned costumes and masks and impersonated evil spirits to instill fear and keep their women subdued. This may explain why females are associated with evil monsters in their culture.
The Patagonian indians in general and the Fuegians in particular did not sculpt stone. They fashioned their spears and tools from bone or stone, wove baskets, braided leather or used rounded stones for their "boleadoras" to capture the local guanaco camelids (or ñandú or rhea "ostriches" on the American mainland).
The few examples of engraved stones, supposedly of a Phoenician origin are an exception (see also alleged Hebrew engraved stones), but are clearly not of the Native American style which are less elaborate (see Genuine Native stone implements).
The stark and simple masks contrast with those elaborate "Middle Eastern" engravings, and also with the strange "Yamana sculpture"; the object does not seem to be a native handicraft.
This strange Yamana sculpture showing a person (with a hat? and a coat?) was probably the outcome of contact with Bridges' mission or maybe it was crafted as part of the activities at the misison. Thomas Bridges does not tell us what sort of work the natives did at the Ushuaia mission (we do know that the crowded settlement and the interaction with the Europeans which began arriving in the early 1880s decimated the canoe people with measles, tuberculosis and flu).
I resist the temptation to suggest that the sculpture depicts some mythical being (a Fuegian dwarf or ogre), because there is no context in which to insert it. Just a photograph in a book with a non descript caption. Such was the work of the anthropologists of the late 1800s!!
Later scholars had the knowledge and the know-how but lacked the subjects: disease had wiped out most of the Yaghans, Alakaluf and also the Selk'nam (or Ona) pedestrian natives that lived inland (actually these had also fallen under the bullets shot at them by the local gold-panners and European sheep farmers: the natives took to hunting sheep, far more easy preys than the guanaco).
Early 1900s postcard depicting a "Fuegian Indian" (No indication is given about the group he belonged to), both he and the Yaghan pictured further down have a certain "Australian" look don't they?
Below is a Yamana native (in mourning), from the French "Mission Scientifique du Cap Horn" (1882-1883) under captain Ferdinand Martial :
 Giacomo Bove, Domenico Lovisato, Expedición a la Patagonia: un viaje a las tierras y mares australes (1881-1882). Ediciones Continente, 2005, pp. 146.
 Guillermo Lagos Carmona Los títulos historicos Andres Bello, 1985 - Chile pp. 34
 Orquera, L. and Piana, E., (1999). La vida material y social de los Yámana. B. Aires: Eudeba
 Claudio Pulgar Pinaud, (2007). Vivienda Indigena, Participación y desarrollo social. El caso de la Comunidad Indigena Kawesqar de Puerto Eden. Revista invi Nº 60, Agosto 2007, Vol. 22: 59 -100
 Infinity of Nations: Art and History in the Collections of the National Museum of the American Indian, Smithsonian.
 Cristopher Agostino, (2011)Masks from here Bark Masks and Bodypainting of the Yamana (or Yaghan) and the Selk’nam (or Ona) of Tierra Del Fuego
 Martial, L., (2005). Mision al Cabo de Hornos, la expedición científica francesa en la Romanche Julio de 1882 a setiembre de 1883.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2014 by Austin Whittall ©