1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

have up to 4 seeds. This species was the only cordate species known to Engler with more than 2 seeds per berry and perhaps too much emphasis was placed on this distinction. Possibly, once living material of this species is available for study it will prove to be more appropriately included in another section.

Anthurium gymnopus was counted by Gaiser (1927) with 2N = 30, however, A. gymnopus has apparently not been involved in hybridization studies.

This section was represented in both Schott's and Engler's treatments by a single species, A. scherzerianum Schott which is well known in cultivation. That species is characterized by its large bright red spathe. Apparently it was on this basis alone that both Schott and Engler placed it in its own section. It otherwise shares identical vegetative characters with many species Engler placed (perhaps erroneously) in his section Urospadix.  In addition all of these species have generally slender stems with short internodes, generally elongate, non-cordate leaf blades which are glandular-punctate at least on one surface. They bear one or more prominent collective veins along the margin (Fig. 4). In addition the berries usually have 3 or more seeds and are frequently depressed at the apex (Fig. 5).

As defined here the section Porphyrochitonium  is a large, presumably natural group of about 250 species (though relatively few had been described by the time of Engler's revision in 1905) and the group with probably the most species new to science. The section ranges principally from Costa Rica to Peru with the greatest concentration of species in northwestern Colombia. Relatively few species are widespread in cultivation, one of the best known being A. bakeri Hook. f. (atypical in having only 2 seeds per berry). Most are relatively small plants. Section Porphyrochitonium is currently being revised by the senior author.

Chromosomally the section is based on 2N = 30. Aneuploids have been reported in A. bakeri Hook. f., A. bicollectivum Croat, A. lancifolium  Schott and A. scherzerianum Schott. Representative includes A. bakeri Hook. f., A. bicollectivum Croat, A. crassiradlx Croat, A. lancifolium  Schott, A. pageanum  Croat, A. paludosum Engl., A. sagawae  Croat, A. scherzerianum  Schott, A. terryae  Standl. & Wms., A. utleyi Croat & Baker and A. wendlingerii  Barroso. Although not all species have been successfully crossed with every other species in the group, gene flow throughout this group has been demonstrated to be possible. Throughout the section, aneuploidy can be expected to have a deleterious effect on fertility.

IV. DIGITINERVIUM Sodiro (Fig. 22 & 23)
This relatively small, seemingly very natural group, is characterized by thick blades with glandular punctations, steeply ascending basal veins (usually two or more pairs extending sharply toward the apex and often reaching well above the middle of the blade) (Fig. 22). It also has transversely oriented and closely parallel tertiary veins extending between the basal veins.

The section Digitinervium  is mostly restricted to the Andes of northwestern South America and the mountains of Costa Rica and Panama. The most well known example of this section is probably A. ovatifolium  Engl. (Fig. 23) (A. "caucanum" of Exotica III, P. 130). Anthurium lentii  Croat & Baker, the only Central American representative of this section, is another example. Other examples include A. crassifolium  N.E. Brown, A. lingua  Sodiro and