We cannot leave out of account the urinary products, which, in the case of dung from hunting kennels, are always present, though in varying quantities. The total nitrogen in 1520 c.c. of urine was found[23] to be 15·9 grm. [23] Abderhalden, Physiological Chemistry. Each 100 grm. total nitrogen was distributed as follows:-- Urea 85·9 NH_{3} 4·1 Creatinine 3·3 Uric acid 0·5 N in other compounds 5·7 The inorganic compounds were:-- Per cent. Sulphur (as sulphate) 3·31 P_{2}O_{5} 3·98 Cl 6·30 The urine of carnivora is acid, that of herbivora is neutral or alkaline. Urea, which is the chief nitrogenous constituent, is very quickly fermented by several species of bacteria, and entirely decomposed into ammonium carbonate, so that it is this latter body which acts in the bate. Uric acid exists in the urine of the carnivora, but the quantity is small compared with the urea. Herbivora excrete, mostly, hippuric acid NHC, H_{5}O / (benzoyl-glycocoll, CH_{2} ), \ COOH and this difference may account to some extent for the difference in bating property, that of the excreta of herbivora being very small as compared with the carnivora, such as the dog. In this respect there are differences which are difficult to account for; for instance, the excreta of the lion, fed entirely on a meat diet, was not found to have such a powerful bating effect as ordinary dog puer. Even after keeping for several weeks, to allow the bacterial flora to develop, the result was the same. The analysis of the lion’s dung gave the following results:-- Per cent. Water 59·2 Ash 21·1 Lime (CaO) 10·3 Phosphates (P_{2}O_{5}) 10·67 Organic matter 19·7 Dog dung contains some non-volatile bases of the purine group, such as xanthin (C_{5}H_{4}N_{4}O_{2}) and guanin (C_{5}H_{5}N_{5}O), but the action of these bodies in the bate, has not been studied. It is also extremely probable that these and similar bodies are formed _during_ the bating by a process of auto-digestion of various proteids.[24] The quantity of _fat_ in dry puer, amounts to 10–11 per cent. Cholesterol was present.[25] Part of the fat is in the form of lime and magnesia soaps, but part in the form of an emulsion, which probably plays an important part in the puering process. The function of the fatty constituents of puer is one of the problems on which further research is necessary. [24] Cf. Mann. Chemistry of the Proteids, 1906, p. 432.