_Infection of the adjacent lymph glands_ is usually found to have taken place by the time the primary lesion has acquired its characteristic induration. Several of the glands along Poupart's ligament, on one or on both sides, become enlarged, rounded, and indurated; they are usually freely movable, and are rarely sensitive unless there is superadded septic infection. The term _bullet-bubo_ has been applied to them, and their presence is of great value in diagnosis. In a certain number of cases, one of the main _lymph vessels_ on the dorsum of the penis is transformed into a fibrous cord easily recognisable on palpation, and when grasped between the fingers appears to be in size and consistence not unlike the vas deferens. _Concealed chancre_ is the term applied when one or more chancres are situated within the sac of a prepuce which cannot be retracted. If the induration is well marked, the chancre can be palpated through the prepuce, and is tender on pressure. As under these conditions it is impossible for the patient to keep the parts clean, septic infection becomes a prominent feature, the prepuce is œdematous and inflamed, and there is an abundant discharge of pus from its orifice. It occasionally happens that the infection assumes a virulent character and causes sloughing of the prepuce--a condition known as _phagedæna_. The discharge is then foul and blood-stained, and the prepuce becomes of a dusky red or purple colour, and may finally slough, exposing the glans. _Extra-genital or Erratic Chancres_ (Fig. 38).--Erratic chancre is the term applied by Jonathan Hutchinson to the primary lesion of syphilis when it appears on parts of the body other than the genitals. It differs in some respects from the hard chancre as met with on the penis; it is usually larger, the induration is more diffused, and the enlarged glands are softer and more sensitive. The glands in nearest relation to the sore are those first affected, for example, the epitrochlear or axillary glands in chancre of the finger; the submaxillary glands in chancre of the lip or mouth; or the pre-auricular gland in chancre of the eyelid or forehead. In consequence of their divergence from the typical chancre, and of their being often met with in persons who, from age, surroundings, or moral character, are unlikely subjects of venereal disease, the true nature of erratic chancres is often overlooked until the persistence of the lesion, its want of resemblance to anything else, or the onset of constitutional symptoms, determines the diagnosis of syphilis. A solitary, indolent sore occurring on the lip, eyelid, finger, or nipple, which does not heal but tends to increase in size, and is associated with induration and enlargement of the adjacent glands, is most likely to be the primary lesion of syphilis. [Illustration: FIG. 38.--Primary Lesion on Thumb, with Secondary Eruption on Forearm.[1]]