The following are a collection of sources that in some way describe the Karankawas’ height. I have chosen to make this category because Karankawas’ are propagandized as being giants. Instead, they were merely taller than average for the time period. I have written an in-depth article on this inaccuracy, all of my sources are found below:
 Juan Enríquez Barroto’s Voyage and Diary
Author: Juan Enríquez Barroto
Written In: 1687
Description: When the Spaniards learned that the French had settled in Texas, they sent numerous expeditions to locate and ultimately destroy the French establishment. Juan Enríquez Barroto served as chief pilot on one of these searches by sea in 1687. He mapped geographical features and recorded all that he saw. Sailing north from Veracruz, this expedition hugged the entire coast of Texas and treated with nearly every Native American group along that coast.
(1) Spaniards attempt to kidnap a Karankawa. With a knife, the Karankawa wounded three of his would-be captors and caused the Spaniards to flee. See April 7th, pg. 173.
(2) A war between the Atakapas and Karankawas during this period is implied. In 1719, a shipwrecked Frenchman who the Akokisas enslaved, validates a conflict between the Akokisas and the Karankawas. See April 23rd, pg 184. And the Simars de Bellisle entry.
(3) The Karankawas geographical range is labeled as from around Aransas Bay to Matagorda Bay. From Corpus Christi southward, Enríquez labels as being the lands of “pelones y rayados” (bald and tattooed), or Coahuiltecans. From Galveston Bay northward, Enriquez labels as being the lands of the Akokisas and Atakapas. Karankawa Indians increased their borders in both directions over time.
Access: Robert Weddle, La Salle, the Mississippi and the Gulf (College Station: Texas A&M Press, 1987) 173-174. I am unable to post a full copy of this text because of fair-use conditions, so I have only uploaded the sections that have relevance to the Karankawas. If additional context is required, contact me.
Further Reading: For more on how the Spaniards learned of the French settlement of Fort Saint-Louis, see Weddle, Wilderness Manhunt: The Spanish Search for La Salle (College Station: Texas A&M Press, 1973), 7-14.
 “Journal of Stephen F. Austin on his first trip to Texas.”
Author: Stephen F. Austin
Written In: 1821
Description: This journal documents Stephen F. Austin’s first travels through Texas. His view on the Karankawas is extremely biased—they are Indians on the land he intends to colonize. Most of his information on the coastal Indians was steeped in Spanish propaganda. Infamously, Austin discusses that “there will be no way of subduing [the Karankawas] but extermination.”
Relevance: See pages 300-305.
Further Reading: Gregg Cantrell, Stephen F. Austin: Empresario of Texas (Austin: Texas State Historical Society, 2016).
[1833-1834] John Charles Beales’s Rio Grande Colony: Letters by Eduard Ludecus, a German Colonist, to Friends in Germany in 1833–1834, Recounting His Journey, Trials, and Observations in Early Texas
Author: Eduard Ludecus
Written In: 1833-1834
Description: Eduard Ludecus and other settlers rest and resupply in La Bahía (Goliad) on their way to settle along the Rio Grande. In the ramshackle city of La Bahia, and in the missions in close proximity, they encounter Karankawas.
(1) Ludecus inaccurately states that “when Colonel Austin’s grant was settled, they [Karankawas] invaded there [Austin’s lands] and killed anyone they found.” This is backward, but it shows that Anglo-Americans, Mexicans, and Tejanos believed this falsity. Ludecus received this information from Holley Austin’s account of Texas (Austin Holley, 95-97). In essence, Ludecus is already biased when he first encounters the Karankawas. He sees these Indians as always looking to steal and murder.
(2) Ludecus then goes on to state that Stephen F. Austin “succeeded in exterminating half the tribe.” A large group of Karankawas fled to La Bahía, where Mexican officials murdered half of the survivors.  As already mentioned, all this information has come from Mary Austin Holley’s Texas. This information is not unique. All the following information that Ludecus provides is unique.
(3) Ludecus refers to Karankawas as “well over six feet tall” and gives a detailed description of their tattoos, piercings, weapons, and dress. [pages 79-86]
(4) Ludecus provides a great deal of information about Chief Prudentia. He also describes that Dr. Beale asks Prudencia whether he and other Karankawas would like to join the settlement. [78-83]
(5) States that Comanches and Karankawas are “mortal enemies” at this time. 
Access: Eduard Ludecus. John Charles Beales’s Rio Grande Colony: Letters by Eduard Ludecus, a German Colonist, to Friends in Germany in 1833–1834, Recounting His Journey, Trials, and Observations in Early Texas, ed. and trans. Louis E. Brister (Austin: Texas State Historical Association, 2008).
Further Reading: For a well-written overview of the Beales colony, see Kyle B. Carpenter, “A Failed Venture in the Nueces Strip: The Mismanagement of the Beales RioGrande Colony, 1832-1836” The Southwestern Historical Quarterly,(Forthcoming Spring 2020); For another source on Cheif Prudentia see Kelly Himmel, The Conquest of the Karankawa and the Tonkawas, 1821-1859 (College Station: Texas A&M University Press, 1999), 52-53.