(_b_) Analgesia is that condition in which painful impressions are not perceived, though common, caloric, or muscular sensibility may be normal or nearly so. Pricking, cutting, and bruising are unperceived. This, the most common variety, is usually met with in hysterical cases; it occurs at a certain stage of general artificial anæsthesia, in chronic alcoholism, extreme emotional states, and in hypnotism. Though a very striking symptom, it is not one of as serious meaning as loss of tactile or thermic sensibility. Often the patient is unaware of analgesia until tests reveal its existence. (_c_) The sensibility of the skin to caloric is usually the last to disappear in the progress of an organic lesion, so that in certain cases (injury to nerves or spinal cord, myelitis, etc.) testing by ice or by a burning object is a sort of last resort. Before deciding in a given case that there is a complete break in the sensory tract, this test should be used as well as the application of the most intense induced electric current delivered upon the dry skin by a wire end. {36} In some cases of partial anæsthesia (_e.g._ in posterior spinal sclerosis) cold may be felt as heat and vice versâ, or pinching may be felt as burning, and be quite persistent. (_d_) The so-called muscular sense may be greatly impaired or lost without ordinary anæsthesia. In such a case the subject is no longer directly and spontaneously aware of the exact position of his limbs, of passive motions done to them, and he executes voluntary movements with uncertainty. He is also unable to judge correctly of differences of weight in objects successively placed in his hand or hung from his foot. He needs the aid of sight to guide the affected limb and to judge of its position, etc. The awkwardness and uncertainty in voluntary movements by impairment of muscular sense must not be confounded, as is sometimes done, with ataxia, in which the attempted volitional movement is jerky and oscillatory, owing to the inharmonious action of antagonistic muscular groups. (_e_) When a strong induced electrical current is passed through a muscle by means of wet electrodes applied to the skin, so as to cause a strong contraction, a special quasi-painful feeling, akin to that of cramp, is experienced in the contracting muscle, and is clearly distinguishable from the cutaneous sensation. This, the electro-muscular sensibility, may be lost independently of other modes of feeling and without loss of contractile power. (_f_) Some observers claim that a special mode of sensibility exists in the skin by which varying degrees of pressure are estimated, independently of traction upon tendons and muscles (muscular sense), and that this may be separately impaired or lost.