Description: This paper is the second (Florsch\xc3\xbctz & Florsch\xc3\xbctz-de Waard 1974) in the series of reports on cryptogams of Colombia, especially the high Andean bryophytes and lichens, in the framework of recent phytosociological and ecological studies in the area by A. M. Cleef and T. van der Hammen (Amsterdam) and his collaborators. The aim of these studies is to prepare comprehensive descriptions of the various Andean biota of Colombia as a basis for an evaluation of the biological diversity of the Andean environment of Colombia. This paper deals with the Hepaticae or liverworts and focuses on the structure of the oil bodies in the liverwort cell and the geographical and ecological distribution of the species.\nThere are few papers on tropical Andean liverworts. The classical work by Spruce (1884-85) included liverworts of the Ecuadorian and Peruvian Andes. A large number of Andean taxa are treated in Fulford\xe2\x80\x99s Manual of the leafy liverworts of Latin America (Fulford 1963, 1966, 1968, 1976) and the latter has been our main source of data on distribution of species. Some ecological notes on tropical Andean taxa are found in the works of Herzog (1934, 1955), Robinson (1967) and Winkler (1976), who for the first time presented a synthesis of liverwort species distribution in relation to Andean vegetation typology in a limited area in Northern Colombia.

Description: El 25 de mayo de 1976 falleci\xc3\xb3 inesperadamente, a la edad de 53 a\xc3\xb1os, Peter Arnold Florsch\xc3\xbctz, eminente bri\xc3\xb3logo y profesor de Bot\xc3\xa1nica Sistem\xc3\xa1tica en Utrecht (Holanda). Era bien conocido por sus estudios de los musgos de Surinam. Fue coauter del "Index Muscorum\xe2\x80\x9d, miembro de la comisi\xc3\xb3n de la Flora Neotr\xc3\xb3pica y tesorero del IAPT.\nDurante sus \xc3\xbaltimos 10 a\xc3\xb1os estudiaba, junto con la se\xc3\xb1ora Florsch\xc3\xbctz, los musgos de los Andes colombianos. En 1972 visit\xc3\xb3 muchas zonas de p\xc3\xa1ramos y selvas andinas, especialmente en los alrededores de Bogot\xc3\xa1 (Cundinamarca), la Sierra Nevada del Cocuy (Boyac\xc3\xa1, Arauca) y el Nevado del Ruiz (Caldas). En 1975 tuvo la oportunidad de visitar nuevamente algunos p\xc3\xa1ramos cercanos a la capital colombiana. Sus colecciones de 1972 y 1975 (con cerca de 1.000 n\xc3\xbameros) se conservan en Bogot\xc3\xa1 (COL) con duplicados en Utrecht (U).

Description: Morphology, chemistry, distribution and ecology of 6 species of Cladonia subgenus Cladina (Lichenes) from the Colombian paramos are described: C. arcuata Ahti, C. boliviano Ahti, C. confusa Sant., C. polia Sant., C. rangiferina (L.) Wigg. var. abbayesii Ahti, and C. colombiana spec. Nov. C. bicolor (Mull. Arg.) Ahti is reduced to synonymy under C. polia.

Description: Oil bodies in leaves variable in number, (2-)3-8(-13) per cell; subglobose to, more rarely, ellipsoid, 4-8(-12)x4\xe2\x80\x946 \xce\xbcm; colourless, rather coarsely to finely granulosepapillose, becoming homogeneous upon degeneration (Colombia, Cundinamarca, Cleef 78b, 3410b, 397b; ibid., Cauca, Cleef 679).\nVariation in number and morphology of the oil bodies apparently is characteristic for Lophocoleaceae, since it has been found not only in this and the other species of Lophocolea reported here but also in European material of Lophocolea and Chiloscyphus (unpubl. obs.).

Description: Fossil pollen grains from the Quaternary of Colombia, formerly provisionally indicated as \xe2\x80\x9cValeriana\xe2\x80\x9d stenophylla Killip, have now been identified as those of the Andean genus Lysipomia H.B.K. (Campanulaceae).\nIn the genus Lysipomia s.l. (fide McVaugh) two considerably different pollen types are found: That of the Lysipomia s.s. and the Rhizocephalum type. The former was probably derived from the latter.

Description: Oil bodies 7-12 in upper leaf cells, 10-20 in elongated basal leaf cells; globose to ellipsoid, 3-7(-10)x3-5 \xce\xbcm; colourless, coarsely segmented, consisting of c. 15-30 aggregated droplets (Colombia, Boyac\xc3\xa1, p\xc3\xa1ramos NW of Bel\xc3\xa9n, Cabeceras Q. El Toral, 3765 m, Cleef 2292e; Ecuador, p\xc3\xa1ramos de El Angel, 17 km. S. of Tulc\xc3\xa1n, 3350 m, Gradstein, Lanier & Weber s.n.).\nThe presence of segmented oil bodies in Colura patagonica is remarkable because previous studies of living Colura (from Japan) reported homogeneous oil bodies (cf. Schuster & Hattori 1964; Inoue 1974).

Description: A phytosociological survey based on methods of the Z\xc3\xbcrich-Montpellier School was carried out in the p\xc3\xa1ramo vegetation of the Cordillera Oriental, Colombia. The study area covers about 10,000 and comprises the p\xc3\xa1ramo between the Nevado de Sumapaz (3\xc2\xb055\'N, 4250 m), the Sierra Nevada del Cocuy (6\xc2\xb025\'N, 5493 m) and the P\xc3\xa1ramo del Almorzadero (7\xc2\xb0N, 4375 m). The p\xc3\xa1ramo vegetation was studied along various altitudinal transects from the upper forest line (3000-3500 m) up to the lower limit of the snowcap (4800 m). A general description of the study area includes data on geology, geomorphology, soils, climate, flora, phytogeography, morphological characters of the vegetation, fauna and landuse. The evolution and Quaternary history of p\xc3\xa1ramo vegetation and climate is reviewed, incorporating the first data from the Lateglacial and Holocene of the P\xc3\xa1ramo de Sumapaz. The general altitudinal zonation of the p\xc3\xa1ramo vegetation was studied and is presented for both the dry and the humid side of the Cordillera. The zonal and azonal plant communities are described including their physiognomy, composition and syntaxonomy, habitat and distribution. Eighty five syntaxa from the rank of variant to that of the class are newly described, 17 of which are provisional. The vegetation is not ranked syntaxonomically yet, but described on the basis of preliminary tables. A number of azonal communities, part of them of lesser extent, are described in a similar way. The p\xc3\xa1ramo vegetation is primarily determined by the tropical diurnal high mountain climate. The diversity of the p\xc3\xa1ramo vegetation is related to temperature (altitudinal gradient) and to humidity (dry and wet climate). The presence of zonal bunchgrass p\xc3\xa1ramo, bamboo-bunchgrass p\xc3\xa1ramo or bamboo p\xc3\xa1ramo mainly depends on the complex interrelation between these factors. Finally a synthesis is provided on ecology, morphology and phytogeography of the p\xc3\xa1ramo vegetation of the study area.