_Causes._ The toxic neuralgias are illustrated by chronic lead poisoning, in which, in man, there are wandering pains like those of rheumatism, and in the lower animals muscular stiffness and contractions which suggest a similar condition. In man, too, gout is a common factor, and in pigs and birds in which this condition exists, stiffness and evidence of suffering may well be at times attributed to a similar cause. How many other forms of chronic metallic poisoning and poisoning by morbid autochthonous products of indigestion are attended by disorders of innervation and nutrition, it is as yet impossible to say. The direct action of cold, an anæmic condition of the nerves, and reflex action from distant sources of irritation are among the other invoked causes. Inflammation in the _nervi nervorum_ is also invoked as a factor, but in this case the symptoms would not accord with the rule given above, since the nerve trunks would be very tender to touch or pressure, and the suffering would be unshifting and shown permanently in the one seat. =Facial Neuralgia.= Lafosse and Zundel describe as cases of this kind those in which periodically the horse’s eyes are fixed and shining, the ears drawn back and depressed as in vice, the head at intervals bent on the neck, with plaintive neighing, rubbing the head on the stall and pawing. Those cases of twitching of the head or rapid jerking of the ears in horses, when they have been driven for some distance, and which are relieved by wearing a close net over the nostril or by section of the trifacial nerve at the infra-orbital foramen, manifestly partake of this character. =Cervico-Occipital Neuralgia.= Lafosse speaks of this as often mistaken for torticolis, the head being turned to the affected side during the paroxysms. In man this is often a result of cold draughts on the back of the head, and associated with tender points on the course of the nerve, between the mastoid and the median line. =Dorso-intercostal neuralgia= causes pain in deep inspiration, and =lumbo-abdominal neuralgia= develops tenderness in the loins, in one testicle, or in one lip of the vulva according to Lafosse. Diagnosis between such cases and neuritis, spinal disease, and other obscure nervous affections must be very problematical. =Sciatic Neuralgia.= This is described by Zundel as causing jerking and lameness in the affected limb, sometimes aggravated and sometimes improved by work and associated with muscular weakness or paresis. Sciatica in man is, however, rarely a simple neuralgia, but partakes rather of the nature of a neuritis, and there is no good reason for supposing that the disease of this nerve in the lower animals is other than an inflammatory condition. Leclainche after consideration of the testimony adduced, is of the opinion that we still lack absolute evidence of uncomplicated neuralgia in the domestic animals.