[47] Bottazzi and Gabrielli: Arch. internat. de physiol. =111=:156, 1905. [48] Enriquez and Hallion: Bull. gén. de thér. =162=:202, 1911. [49] Falloise: Bull. de l’Acad. roy. de Belgique =5=:945, 1902. [50] Bayliss and Starling (Note 2). Matuso (Note 6). Arch. internat. de physiol. =10=:335, 1911. [51] Dixon and Hamill: Jour. Physiol., 1909, xxxv, 314. [52] Bayliss and Starling: Jour. Physiol., 1904, xxx, 61. Bierry: Compt. rend. Soc. de biol., 1907, lxii, 433. Bierry and Terroine: Compt. rend. Acad. de sc., 1905, cxli, 146. Lalou: Comp. rend. Acad. de sc., 1910, xxix, 824. Morel: Compt. rend. Soc. de biol., 1909, lxvii, 36. Strassano and Billoro: Compt. rend. Soc. de biol., 1902, liv, 937. [53] Bayliss and Starling (Note 23). _Specificity._--In a maceration of the duodenojejunal mucosa, such as we have in secretin, the known substances are proteoses and peptones, acid amins, bile salts, beta-imidazolethylamin, cholin, gelatin and inorganic salts. These substances, individually and severally, together with their derivatives, are devoid of secretory action. Chemically, secretin, is then a specific entity. But like epinephrin, in its distribution, it is nonspecific. Active preparations have been made from an extraordinary variety of animals among the different classes of vertebrates (Camus,[54] Bayliss and Starling,[55] Chapman[56]). It is likewise found in the new-born and in the fetus.[57] Its action, however, like its chemical composition, is markedly specific. It stimulates the flow of pancreatic juice, bile and succus entericus. Its effect on the gastric glands is negative, and on the saliva likewise.[58] On the other hand, no other extracts produce pancreatic secretion. Dr. Koch, who, in collaboration with Dr. Keeton and Dr. Luckhardt, has done the most recent work on gastrin[59] (a substance that most nearly resembles secretin) and has isolated an extremely active preparation, finds that gastrin injection has likewise no effect on the pancreas. Camus and Gley,[60] with crude preparations, had previously obtained a similar result. [54] Camus: Jour. de physiol. et de path. gén. =4=:998, 1902. [55] Bayliss and Starling: Jour. Physiol. =29=:174, 1903. [56] Chapman: Proc. Linnaean Soc., New South Wales =1=:92, 1905. [57] Camus: Compt. rend. Soc. de biol. =61=:59, 1906. Hallion and Lequex: Compt. rend. Soc. de biol. =61=:33, 1906. [58] Derouaux: Arch. internat. de physiol. =3=:44, 1905. Lambert and Myer: Compt. rend. Soc. de biol. =54=:1044, 1902. Starling: Lancet, London =2=:501, 1905. [59] Keeton and Koch: Am. Jour. Physiol. =37=:481, 1915. [60] Camus and Gley: Compt. rend. Soc. de biol. =54=:648, 1902.