[309] The _Pirrauru_ custom excepted. In this place a somewhat extensive digression concerning the _Pirrauru_ custom must be made. This question plays such an important part in all speculations about a former state of group marriage, and it is undoubtedly such an interesting fact by itself, that it would be impossible not to give here an account at least of its most essential features. The custom in question consists in the fact, that in certain of the South-east Central tribes a man and a woman are put into a relationship which involves occasional sexual connection and some other mutual rights and obligations, to be discussed in detail below. This custom is found in the tribes living North, South and East of the Lake Eyre, the Urabunna, the Dieri, Yantruwunta,[310] and other kindred tribes. We know the most about the Dieri, whom Howitt chooses and represents as a typical example of all these tribes, and whose _Pirrauru_ practices in his opinion differ only slightly from those of the neighbouring tribes. This is important, for our knowledge about the Dieri practices is much more ample than in the case of any other tribe; and it does not agree in all particulars with what we are told about the Urabunna by Spencer and Gillen.[311] We shall, therefore, rely in the first place upon the information given about the Dieri by Howitt, Gason, and Siebert, and in our general view of the _Pirrauru_ we shall be guided by this information. [310] For a detailed enumeration and description of all tribes among whom practices of the _Pirrauru_ type exist, see Howitt, _J.A.I._, xx. pp. 31-34. In this article, which is nearly exactly reproduced in Howitt's last work (_Nat. Tr._), we possess, undoubtedly, the best information about the _Pirrauru_ custom. In another place (_Folk-Lore_, xviii. p. 184), Howitt assigns a still wider area to the _Pirrauru_ practice. "Altogether, Dr. Howitt reckons that the tribes which practised a form of group marriage like the _Pirrauru_ of the Dieri must have occupied an area of some 500,000 square miles, extending for a distance of 850 miles from Oodnadatta, the northern boundary of the Urabunna, to the eastern frontier of the Dieri, or of the Mardala tribe between the Flinders Range and the Barrier Range."--Frazer, _Tot. and Exog._, i. p. 371. [311] We have reasons to doubt whether these authors were as well informed about the Urabunna tribe as about the Arunta nation. Anyhow, the information they give about the _Piraungaru_ custom is much inferior as well in respect of quantity as quality (the inconsistency of their statement is shown above) than that about the Arunta, and the conclusions they draw therefrom are not quite in accord with the facts as they relate them (see below, p. 118).