392 W. LANGDON BROWN. 



safrauin, and iu its resistance to prolonged tryptic action. It 

 swells up, however, under the action of this enzyme. It is 

 markedly insoluble, showing no diminution in bulk on addition 

 of weak or strong acids and alkalies, cold or boiling. The only 

 exception to this is concentrated sulphuric acid, which causes 

 it to swell up, and after boiling for a short time to dissolve with 

 an accompanying pink coloration, soon passing toalight brown. 

 No leucin, peptone, or sugar could be demonstrated as a 

 product of this action. 



These reactions remind us somewhat of the insoluble residue 

 described by Schafer^ as obtained from the entostemite of 

 Limulus. The total amount, however, is but slight. 



An artificial pancreatic digestion of mesoglcea yields the 

 results which might be anticipated from the foregoing. The 

 residue was composed of antialbumid (soluble in 1 per cent, 

 caustic soda) calcareous matter (readily soluble in dilute acetic 

 acid) and the granular substance just referred to. The filtrate 

 yielded albumoses, peptones, a reducing sugar, crystals of 

 leucin and of tyrosin — the last presumably from the cells, 

 since in them alone is Millon's reaction successful. 



IV. In investigating a material like the mesoglcea two ques- 

 tions naturally suggest themselves: does it contain gelatine? 

 and does it contain nucleo-albumen? («) Does the mesoglcea 

 contain gelatine? In some experiments on this point, thin 

 slices of mesoglcea were treated with distilled water under 

 pressure at 120° C. for over two hours; in others, portions of it 

 were minced and boiled with distilled water for 1^ hours. The 

 subsequent procedure was that described by Young^ for retiform 

 tissue. The extract was filtered, while boiling, through a hot 

 filter into alcohol. The precipitate which formed was collected 

 after standing for some hours, dissolved in distilled water, 

 boiled, and filtered. The filtrate was concentrated to a very 

 small bulk. In all cases this did not "jelly" perceptibly. 

 Hence we conclude — 



1 Scliiifer, foot-note to Ray Lankester on " Skeleto-tropliic Tissues," 

 ' Q. J. M. S.; vol. xxiv. 



2 R. A. Young, 'Journal of Physiology,' vol. xiii. 



