=Lymphatic Involvement.=--Soon after the appearance of the primary sore, or coincident with it, the enlargement of the adjoining lymphvessels and nodes begins. This is noted first in those which are in closest communication with the site of the chancre, usually in the groin. Occasionally thickened lymphvessels may be felt as cords extending along the dorsum of the penis. There may be enough involvement of the perivascular spaces to produce this appearance and sensation even around the bloodvessels. This lymphatic involvement is exceedingly significant, and yet may be found to some degree after chancroid and even after herpes of the genitals. It is, of course, an expression of a travelling infection--in the first case produced by the syphilitic virus; in the second, by the chancroidal virus; and in the third, by ordinary pyogenic organisms which enter through the pathway afforded by the herpes. The involved lymph nodes of syphilis suppurate much less often than do those of chancroid, and suppurating bubo is, therefore, not common in syphilis. The term _bubo_ generally means an involvement of the lymphatics in the groin, although, strictly speaking, it implies a similar condition in any part of the body. _Syphilitic bubo_, therefore, is to be distinguished from chancroidal as well as from non-specific bubo. These lymphatic lesions are sometimes spoken of as constituting the characteristic _adenopathy_ of the disease, but this is an unfortunate expression, as it implies _glandular_ involvement, and the term lymph gland should never be used, since the structures are not glandular in any respect. The enlargement and persistence of these lymph nodes constitute peculiar features of the disease, and may be noted long after the subsidence of active manifestations.