The emphasis of the order as a constructive and decorative feature has been traced back by some students to the Dorian people’s primitive custom of worshipping in groves. The religious ceremonies, which included a procession of the worshippers, would be conducted amid the trees surrounding the altar or shrine, and in time a roofing of cross pieces thatched with boughs may have been attached to the trees. Accordingly, those who adopt this view suggest that when the use of a grove was succeeded by a constructed temple, the original feature was the peristyle. And possibly there is a commemoration of this in the peristyle of the Parthenon, where a procession of worshippers of the goddess is represented in the sculptured frieze that embellishes the outside of the walls of the cella--thus embodying in the most highly developed form of Hellenic temple its origin in primitive religion. The character of the form seems to have originated in wood construction, certain features of which--to be referred to later--were retained after stone or marble was employed and were translated into details of decoration. The gradual transition to materials of construction, less at the mercy of fire, is hinted at by Pausanias, a Greek geographer and writer on art of the second century <small>B.C.</small>, in his description of the =Heraion= or =Temple of Hera= (Juno) at =Olympia=, the oldest known example of a Doric Temple, attributed to 1000 <small>B.C.</small> The cella wall, he says, was constructed of sun-dried bricks on a lower course of stonework, but the entablature was still of wood, covered with terra-cotta. One wooden column was still standing in the _opisthodomos_, but elsewhere as the wooden columns decayed they had been replaced by stone ones; the design of their capitals showing that the work of restoration lasted from the sixth century to Roman times. The roof was covered with tiles. The cella was divided into a central _nave_ and _side-aisles_ by two rows of columns for the support of the roof, and the aisles were intersected by small screen walls; thus forming alcoves, corresponding to the side-chapels of a Gothic cathedral. In one of these alcoves German explorers in 1878 discovered the _Hermes_ of Praxiteles, which is probably the only marble statue in existence that was actually wrought by the hands of one of the great sculptors. =Early Doric Examples.=--The Dorian migration pushed down through Macedonia and Thessaly into the peninsula of Greece and spread through the islands of the Ægean as far as Crete, afterward planting colonies at =Pæstum= and other sites in Southern Italy and at =Syracuse=, =Selinus=, and =Agrigentum= in Sicily. Throughout all this wide area they carried their particular style of Order--the Doric. In developing it, they brought into play what has been judged their distinguishing trait of character--sense of proportion.