GROIN, REGION OF TILE, (Surgical Anatomy.) (Fr. l'ainc, region inguinale.) The limits of this region, as understood by most surgical writers, seem to be wholly artificial. The groin constitutes the confines of the ab domen and the thigh ; and l'oupart's ligament forms a natural line of division between its femoral and its abdominal portions. A line drawn horizontally, the subject being erect, from the anterior superior spinous process of the ilium to the Linea alba, forms the superior limit of this region, while below it may be defined by a line parallel to the former one, and extending from the pubis to the outer part of the thigh. For the particulars of this region, see Mama, FEMORAL ARTERY, ABDOMEN, and TIIIGII, REGIONS OF 711E.
(R. B. Todd.) I I iEMATOSINE, (alp.a.,blood, and °nIrsco, to fiat.) The colouring matter of the blood.t This principle separates with the fibrine of the blood when that fluid coagulates, and may be obtained free from adherent albuminous matter by the process recommended by Berzelius, which is as follows. The coag-ulum is first to be sliced in thin pieces with a sharp knife, and then carefully washed in separate portions of distilled water; by these means we separate the adherent serum, and if the washing is gently performed, but little htrinatosine be comes washed away with it. The slices thus prepared are placed on a filter and allowed to drain : when the draining is complete, the slices are to be thrown into a glass vessel and broken up in distilled water; we thus procure a solution of the colouring matter while any fibrine pm sent gradually subsides. The liquor when poured off is a tolerably pure solution of leniatosine. If it is wished to procure the principle in the solid form, the solution may be evaporated at a temperature not exceeding 100° Fahrenheit.
Engelhart prefers heating the solution after filtration to about 150° Fahrenheit, which deter mines the precipitation of the Immatosine, while any albumen which may possibly exist in solution with it, remains dissolved at that temperature. Engelhart's process yields us Immatosine in its purest form, but when thus obtained it is no longer soluble in water, if procured by evaporation at 100° Fahrenheit, It is still soluble, and what is very extraordinary, dry hirmatosine procured at that temperature, though it be afterwards subjected to a heat of 212°Fahrenheit, does not lose its property of dissolving in water. Ilwmatosine
may be described under two forms, viz. in solution and in the dry state.
The aqueous solution of hwmatosine is pre cipitated by alcohol and the acids. The alkaline hydro-sulphurets and sulphuretted hy drogen change the colour of the solution to green ; nearly all the metallic and earthy salts precipitate it. Infusion of galls produces a pale red precipitate; gallic acid, however, does not show this effect. Chlorined through a solution of lnematosine passed it. Bromine produces a similar result, but it is some time before the effect is observed. Iodine Will also decolorize the solution after some hours, and produces a brown precipitate, which is found to contain iodine.
Hamatosine when dry is of a dark red co lour and exceedingly hard, having a vitreous fracture. Its chemical properties in many re spects resemble those of fibrine, and albumen in the coagulated state. Berzelius remarks that, like fibrine, it contains a fatty matter pe culiar to itself which can be separated by ether; this is one point of resemblance in the opinion of that chemist. The action of acetic acid on heematosine is a very striking point of resem blance between that body and fibrine; for when the acid in the concentrated state is al lowed to remain in contact with hzematosine for a few hours, we observe that it is converted into a tremulous brown mass which is more or less soluble in water, and which during solu tion evolves nitrogen gas. The nitric, hydro chloric, and sulphuric acids, if diluted with an equal bulk of water, and digested on llama tosine, become coloured yellow and disengage nitrogen ; but they do not dissolve the prin ciple even at a boiling heat. The results of such digestions, however, in the hydrochloric and sulphuric acids, are soluble in Inter; but that which has been digested in nitric acid remains insoluble.