2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/149819We give a classification and a construction of all smooth $(n-1)$-dimensional varieties of lines in ${\bf P}\sp n$ verifying that all their lines meet a curve. This also gives a complete classification of $(n-1)$-scrolls over a curve contained in $G(1,n)$.Plain TeX, typeset by Textures 1.5, 13 pagesAlgebraic Geometrytext