with modifications imposed upon them by the material in which they were first shaped. But all materials other than clay are exceedingly intractable, and impress their own characters so decidedly upon forms produced in them that ultimate originals, where there are such, cannot often be traced through them.

It will be most interesting to note the influence of these peculiarities of originals upon the ceramic art.

A nation having stone vessels, like those of California, on acquiring the art of pottery would use the stone vessels as models, and such forms as that given in Fig. 466 would arise, a being in stone and b in clay, the former from California and the latter from Arizona.

Similar forms would just as readily come from gourds, baskets, or other globular utensils.

Nations having wooden vessels would copy them in clay on acquiring the art of pottery. This would give rise to a distinct group of forms, the result primarily of the peculiarities of the woody structure.

Thus in Fig. 467, a, we have a form of wooden vessel, a sort of winged trough that I have frequently found copied in clay. The earthen vessel given in Fig. 467, b, was obtained from an ancient grave in Arkansas.

Fig. 466.—Form derived from a stone pot.

Fig. 467.—Form derived from a wooden tray.

Fig. 468.—Form derived from a horn spoon.

Fig. 469.—Form derived from a bark vessel.

The carapace of some species of turtles, and perhaps even the hard case of the armadillo, could be utilized in a similar way. The shaping of a knot of wood often gives rise to a dipper-shaped vessel, such as may be found in use by many tribes, and is as likely an original for the dipper form in clay as is the gourd or the conch shell; the familiar horn vessel of the western tribes, Fig. 468, a, would have served equally well. The specimen given in b is from Arkansas. As a rule, however, such vessels cannot be traced to their originals, since by copying and recopying they have varied from the parent form, tending always toward uniform conventional shapes.

A vessel of rectangular outline might originate in wood or bark. In Fig. 469, a, we have a usual form of bark tray, which is possibly the prototype of the square-rimmed earthen vessel given in b.

Fig. 470.—Form originating in basketry.

Fig. 471.—Form originating in basketry.

Fig. 472.—Form originating in basketry.

Basketry and other classes of woven vessels take a great variety of forms and, being generally antecedent to the potter's art and constantly present with it, have left an indelible impression upon ceramic forms. This is traceable in the earthenware of nearly all nations. The clay vessel is an intruder, and usurps the place and appropriates the dress of its predecessor in wicker. The form illustrated in Fig. 470, a, is a common one with the Pueblo peoples, and their earthen vessels often resemble it very closely, as shown in b. Another variety is given in Fig. 471, a and b. These specimens are from southwestern Utah. Fig. 472, b, illustrates a form quite common in the Southern States, a

section in which pouch-like nets and baskets, a, were formerly in use and in which the pots were often modeled.

INVENTION OF FORM.

In the early stages of art, forms are rarely invented outright and I shall not stop to consider the subject here.

MODIFICATION OF FORM.

The acquisition of new materials, the development of new uses, the employment of new processes of manufacture, and many other agencies lead to the multiplication of forms through modification. The processes by which highly differentiated forms are reached are interesting throughout and repay the closest study.

A preliminary classification of the various causes that lead to modification is given in the following synopsis:

MODIFICATION BY ADVENTITION.

Incapacity of