ALLANTOIN. 717 



of such a formation. 1 An endogenous as well as an exogenous origin 

 of oxalic acid has also been suggested. 



Oxalic acid is best detected and quantitatively determined according 

 to the method suggested by SALKOWSKI : Shaking out the oxalic ^acid from 

 the acidified urine by means of ether. Detailed account of this can 

 be found in WEGRZYNOWSKi. 2 



xNH.CH.HN.CO.NH 2 , 



Allantoin (GLYOXYLDIUREIDE) , C4H6N4O.3, OOC | 



N NH.CO 



occurs, it is claimed by earlier writers, in the urine of children within the 

 first eight days after birth, and in very small amounts also in the urine 

 of adults (GUSSEROW, ZIEGLER and HERMANN). It is found in rather 

 abundant quantities in the urine of pregnant women (GUSSEROW). 

 According to WIECHOWSKI the urine of adults, if it contains any allan- 

 toin at all, has only traces, and he could not detect any in the urine of 

 nurslings or in the amniotic fluid, which does not agree with previous 

 reports. Allantoin has also been found in the urine of suckling calves 

 (WOHLER), in urine of oxen (SALKOWSKI), and sometimes in the urine of 

 other animals (MEISSNER). WIECHOWSKI has found it in relatively 

 large quantities in the urine of the dog, cat, rabbit and monkey, and he 

 considers that allantoin is a terminal metabolic product in these ani- 

 mals. It is also found, as first shown by VAUQUELIN and LASSAIGNE, S 

 in the allantoic fluid of the cow (hence the name). That allantoin is 

 formed from the uric acid in mammalia is almost certain, and the inves- 

 tigations on which this is based have already been given in discussing the 

 decomposition of uric acid. 4 The allantoin thus originates from the 

 purine bodies, and consequently in dogs and other animals the excretion 

 of allantoin is considerably increased, according to MINKOWSKI, COHN, 

 SALKOWSKI, and MENDEL and BROWN, S after feeding thymus or pan- 

 creas. A strong allantoin excretion is also found in dogs after poisoning 

 with hydrazine (BoRissow), hydroxylamine, semicarbazide, and amino- 

 guanidine (POHL), and this increase in the excretion of allantoin is 



1 See Wiener, Ergebn. d. Physiol., 1; Tomaszewski, Zeitschr. f. exp. Path. u. Ther., 

 7; Pohl, ibid., 8; Jastrowitz, Bioch. Zeitschr., 28. 



2 Zeitschr. f . physiol. Chem., 83. 



3 Ziegler and Hermann, see Gusserow, Arch, f . Gynakol., 3 both cited from Huppert- 

 Neibauer, Harn-Analyse, 10. Aufl., 377; Wohler, Annal. d. Chem. u. Pharm., 70; 

 Salkowski, Zeitschr. f. physiol. Chem., 42; Meissner, Zeitschr. f. rat. Med. (3), 31; 

 Lassaigne, Annal. de Chim. et Phys., 17; Wiechowski, Hofmeister's Beitrage, 11, and 

 Arch. f. exp. Path. u. Pharm., 60, and Bioch. Zeitschr., 19 and 25. 



4 See footnote 2, page 706. 



6 Minkowski, Arch. f. exp. Path. u. Pharm., 41, and Centralbl. f. innere Med., 1898; 

 Cohn, Zeitschr. f. physiol. Chem., 25; Salkowski, Centralbl. f. d. med. Wissensch., 

 1898; Mendel and Brown, Amer. Journ. of Physiol., 3. 



