=Transfusion of Infants.=--The technique of transfusions performed upon children over the age of about four years does not differ from that used for adults, except that less blood is to be given. The antecubital veins are much smaller and a finer cannula may have to be used, but this is the only source of trouble. The transfusion of infants and very young children may, however, be found to be much more difficult. The operation will have to be done for conditions such as melæna neonatorum, which was discussed on p. 48 of the present work, or for post-operative collapse, such as may follow an operation for congenital hypertrophic stenosis of the pylorus, for intussusception, or for some of the more extreme cases of harelip and cleft palate. In all such instances the transfusion will be a matter of some urgency. Speed and certainty will depend on previous knowledge of the best method to be employed. In the case of melæna neonatorum treated by R. D. Laurie, which has been already referred to, a needle was introduced into one of the antecubital veins, and 20 cc. of citrated blood were injected with a syringe. This method, however, is not to be recommended, on account of its great difficulty. The method used by Helmholtz and also by Howard depends on the introduction of a syringe needle into the superior longitudinal sinus through the anterior fontanelle. A needle two to three inches long attached to a 20 cc. syringe is inserted near the upper angle of the fontanelle at an angle of about 25° with the scalp. As the needle pierces the wall of the sinus, a sensation of resistance is experienced, similar to that given by the piercing of the dura mater in doing a lumbar puncture. Blood should then be allowed to enter the syringe in order to demonstrate that the point of the needle really is lying in the sinus. Abnormalities have occasionally been met with, in which the sinus was situated to one side of the middle line or was very much smaller than usual. The danger of injecting the blood in such a case into the brain or the subdural space need not be emphasized. Difficulty may also be caused by restlessness on the part of the child, and to overcome this Helmholtz has devised an apparatus which grips and fixes the child’s head at a suitable angle. All this, however, makes the process unnecessarily elaborate. As an alternative, Vincent has exposed one of the internal jugular veins into which he introduces a cannula. This again is a comparatively difficult operation, which may leave a permanent scar in a conspicuous place. Vincent had previously used the femoral vein, but he found this difficult to approach, and the wound was apt to become contaminated afterwards.