The Taxaceae are characterized by a unique reproductive structure that has fueled prolonged and insightful discussion about interpretation and origin of the complex compound megasporangiate strobilus of other conifers (Buchholz, 1934, 1948; Chamberlain, 1935; Coulter & Chamberlain, 1917; Florin, 1931, 1948c, 1951, 1954; Gaussen, 1979; Janchen, 1949; Keng, 1969; Pilger, 1903, 1916a, 1916b, 1926; Robertson, 1907; Sahni, 1920; Saxton, 1934; Sugihara, 1943, 1946; Sporne, 1965; Wang et al.
The Taxaceae aril is the fleshy part of the megasporophyll and the apex of the axillary shoot (Chamberlain, 1935; Coulter & Chamberlain, 1917; Florin, 1954; Wilde, 1944).
The microsporangiate strobilus of gymnosperms is simple, but within the Taxaceae and the Cephalotaxaceae there are clear examples of compound pollen strobili, and those that appear simple are currently interpreted to be reduced compound structures (Keng, 1969; Wilde, 1944, 1975).
In most species of Taxaceae the mature plants are profusely branching, spreading shrubs or small trees.
New discoveries and continued floristic work, particularly in China, have added to our body of knowledge on the Taxaceae (Buchholz, 1948; Chen & Wang, 1978, 1984; Cheng, 1934, 1947; Cheng & Fu, 1975; Cheng et al.
The Taxaceae are a family of five genera and 25 species (including 2 artificial hybrids) distributed in the northern hemisphere except for the monotypic Austrotaxus, which occurs in New Caledonia, and one species of Taxus in Indonesia [ILLUSTRATION FOR FIGURE 1 OMITTED].
The Taxaceae are distinguished from other conifer families (except for Cephalotaxaceae) by compound pollen strobili or simple structures derived from compound pollen strobili, peltate microsporophylls, and solitary, terminal ovules embedded in a fleshy closed or open aril.
Applying the principles that the root is more likely to bear ancestral features and that the resin canal is primitive among conifers (Jeffrey, 1903) led Bliss (1918) to contend that the Taxaceae are the most modern gymnosperm family.
The principal area of disagreement among gymnosperm taxonomists concerning the Taxaceae has been the evolutionary position of the family in relation to other groups of conifers.