Worse, every source that even vaguely hints of where to look for the information outside of other authors’ copies of Lowery has contradictory material. The nearest citation in Lowery, coming a paragraph later, is to page 147 of “Navarrete,” by which he means the Colección de los viages y descubrimientos que hieieron. Navarrete speaks himself of this on page 58. Here is the relevant text:
Llamábase la provincia de Amichel: tierra buena, apacible, sana, provista de muchos bastimentos y frutas: sus habitantes traian muchas joyas de oro en narices y orejas; era gente amorosa y dispuesta para recibir la doctrina religiosa y política: su estatura variaba segun la diversidad de provincias. En unas dicen que vieron gente agigantada, en otras de estatura regular, y que en algunas eran casi pigmeos.
It was called the province of Amichel: good land, peaceful, healthy, and provided with many supplies and fruit: people wore much gold jewelry in their noses and ears; the people were loving and willing to receive religious and political indoctrination: The peoples’ heights varied according to the diversity of the provinces. In some, they said that they saw gigantic people, in others those of average height, and that some were almost pygmies.
The footnote tells us to see the primary sources, which are given on, yes, page 147ff. This is the account of Pineda’s boss, Galay, as preserved in a royal decree of 1521 giving him the right to colonize Amichel. Finally, success! The text gives us the same material Navarrete had summarized before, but with more detail that I’m sure you don’t care about. The relevant clauses are as follows:
…é que hay gente en alguna parte desta tierra muy crecida de diez á once palmos en alto, y otra gente baja, é otra gente muy baja hasta cinco ó seis palmos…
…and that somewhere in this land there are very tall people at ten or eleven palms in height, and other people shorter, and still other people very short at five or six palms…
However, while this seems superficially to support the idea that Pineda saw giants and pygmies, the important thing is to go all the way back to the beginning of the interminably long Spanish sentence, whose relevant clause, introducing a long series of “é que” (“and that…”) clauses. The grammar of the sentence does not make clear whether Galay asserted on his own authority that there were giants and pygmies or whether, as with the other “and that” clauses, he was following “segun que los indios,” according to the Indians. As I read the sentence, the information about the giants and pygmies seems to have come secondhand from Native informants; i.e., it’s a myth.
Diego Ribero included the phrase “Rio de Gigantes” (Giants’ River) on a 1529 map of the world, applied to a region Pineda explored, apparently on the strength of this account. It’s now the Rio de Palmas.
The interesting thing is that Navarrete’s use of the words “gigantic” and “pygmy” have influenced later writers, who have applied them indiscriminately, despite the primary source—the royal patent—not using those words. In Spain, a palm was about 8.2 inches (though it varied prior to partial standardization in 1801), so the “pygmies” were about 4 ft. tall, while the “giants” came in between 6.8 and 7.5 feet, as estimated, apparently, from a distance. This is still tall, but not impossibly tall, and more likely is a slight exaggeration of well-fed people who were perhaps a bit above 6 feet in height—assuming they actually existed. The gold-laden rivers and gold-covered Indians did not exist, so I am not sure I would vouch for the giants just yet, though the nearby Karankawans were often said to be very tall, at more than six feet.