No general, regional name was ever applied to these Indians, but a few individual rancheria names have been preserved. These are all designated in the San Francisco Baptism Book as lying on the "otra banda del estero" (or some similar expression):
| 1778: | paraje | Halchis |
| 1779: | paraje | Chapugtac |
| paraje | Tupucantche | |
| 1780: | rancheria | Genau (or Chynau) |
| rancheria | Tupine | |
| 1780: | rancheria | Itenau |
| rancheria | Tumiamac | |
| 1781: | rancheria | Torqui |
| 1782: | rancheria | Putnatac |
| rancheria | Ocquizara | |
| rancheria | Tacomui | |
| 1784: | rancheria | Ssichitca |
| araje | Cosopo | |
| 1786: | rancheria | Ilorocrochay |
| paraje | Guet |
These records show, first, that from 1778 to 1786 the missionaries from San Francisco recognized fifteen inhabited places along the southeast shore of the Bay. Second, it is very clear that active search for converts was proceeding during these eight years Finally, the field must have been substantially exhausted because none of the fifteen localities are noted after 1786.
Nevertheless, San Francisco did not get all the natives, because Santa Clara was much closer and was active during the same period Unfortunately we cannot determine the village of origin for these neophytes, since the baptism book (according to Pinart's transcript) allocates the individual converts to rancherias, not according to the native names of the latter, but by corresponding Saint's names, which must have been applied, Mexican fashion, by the local missionaries Only after 1801 did Santa Clara change its system, and of course by this time no heathen Indians remained locally.
San José was founded and began conversions in 1797. The baptism book here has the converts identified according to general area, not specific village. There are six such regions, or categories: "Palos colorados," "de la Alameda," "del Estero," "del Norte," "del Este," "del Sur." Of these the first three are evidently local and in the region now being discussed: (1) the redwoods back of Oakland and San Leandro; (2) Alameda Creek and adjacent plain; (3) the shore of the Bay directly west of the mission. The conversions, 1797-1802 inclusive, from these three areas were respectively 31, 170, 130, indicating that San Francisco and Santa Clara had by no means completed the conquest.
Area 2. The coast from Richmond to Carquinez Strait.—That this strip was held by the tribal group known as Huchiun (Cuchillones, Juchillones) has been supported by the accounts of Amador (diary of 1797) and of Abella (diary of 1811). The latter writer, it will be remembered, renamed the Point of the Huchines, Point San Pablo, a name which it retains today. The point of the Abastos or Aguastos became Point San Pedro. The Abastos, it may be pointed out, were neither Costanoan nor resident on the east side of the Bay. They lived on the Bay shore of Marin County, as is abundantly evident from the San Francisco baptism records.
The Huchiun are mentioned by Chamisso and by Choris (Mahr, 1932) in 1816, jointly with various other North Bay tribes. Chamisso says that the Utschíun, together with the Guyment, Olumpalic, Soclan, and Sonomi, all speak the same language, a manifest error. Choris repeats the mistake. Arroyo de la Cuesta gives a Huichun vocabulary and says (1837; MS p. 21) "Karquin and Huichun is one language—Saclan is another, entirely distinct." The Huchiun are noted in the San Francisco records first in 1787 (Tuchiun) and subsequently repeatedly until 1809, although they never appear in the San José record. Apparently San José derived converts from the east rather than from up coast.
The exact limits of the Huchiun are doubtful. Amador spent a night somewhere near Richmond and then went north to find them. Abella associates them closely with Point San Pablo, and implies that their land reached as far as the strait. We may tentatively draw their boundary between Rodeo and Crockett.
Area 3. Carquinez Strait and Concord Valley.—We are dealing here with the shore line from Crockett through Martinez nearly to Pittsburg, and inland between Concord and Pacheco. The principal Indian name associated with this area is Karquin, from which the strait takes its name. Just what group of people is involved is a puzzling question.
Kroeber, in the Handbook of California Indians (1925, pp. 356, 466), includes the Karkin as a division of the southern Wintun, which would mean that the principal seat of habitation was north of the strait. While there is no evidence in the early records to exclude this completely, there is certainly no question that at least a portion of the group lived on the south side. Thus the mission records before the settlement of the north shore report numerous baptisms of Karquines or Tarquines. Viader (1810) camped near Martinez, where the rancheria of the Tauquines used to be. Arroyo de la Cuesta says the language of the Karkin is the same as (or similar to) that of the Huchiun. The latter is Costanoan: the former could not be Wintun. The name Karkin was said by Arroyo de la Cuesta to signify "trocar," or "to trade." It has been supposed that the reference is to the rancheria which traded with Cañizares and other early explorers.