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era, Jugastrum, Holopyxidium, Berthoiletia)

Subfamily III:

Napoleonoideae

Tribus III,:

Napoleoneae (Napoleonaea)

Tribus III2:

Craterantheae (Crateranthus)

Tribus III3:

Asterantheae (Asteranthos)

Pichon (1945) gives floral, fruit, seed, and embryo characteristics for each subfamily and tribe. Melchior (1964) follows Pichon without modification.

Embryological differences between the Myrtaceae and the Lecythidaceae were pointed out by Treub (1884), Mauritzon (1939), and Venkateswarla (1952). Mauritzon states "Personally I am unable to find with the aid of embryology any evident connecting link between any of the Lecythidaceae and any other family of Myrtles." The principal embryological differences bet-tween the Myrtaceae and Lecythidaceae are the large nucellus and thick integuments (2 cells thick) of the former and the scanty nucellus and thick integuments of the latter. Since these studies only include species of Barringtonia, Gustavia, Couroupita and Napoleonaea there is a great need for further embryological study of the family. Information on staminal development has been provided by John McLean Thompson (1921, 1927), who concluded that the stamens develop centrifugally. As has been demonstrated by Payens (1967), embryo structure differs between genera and hence is of taxonomic importance. Payens found that the embryo of Barringtonia lacks true cotyledons, possessing instead tiny scales at the apical end. Essentially the same structure is found in Careya (Thomson, 1858), Chydenanthus (Treub, 1884), Abdulmajidia (Whitmore, 1974), Berthoiletia (Goebel, 1905; Payens, 1967), Eschweilera (Berg, 1858, Duke, 1969, Prance and Mori, 1978); and Lecythis (Duke, 1969; Prance and Mori, 1978). In contrast, well-developed cotyledons are found in Cariniana (Payens, 1967; Prance and Mori, 1978), Petersianthus (Pichon, 1945), Couratari (Poiteau, 1825; Knuth, 1939b, Duke, 1969), Couroupita (Poiteau, 1825; Knuth, 1939b; Payens, 1967), Gustavia (Poiteau, 1825; Woodson, 1958; Mori, 1974), and Planchonia (Knuth, 1939a; Kartawinata, 1965).

The palynologist Muller (1972) recognizes two types of pollen in the family, the Planchonia main type (syntricolpate) and the Lecythis main type

(tricolpate). According to Muller, pollen morphology supports the division of the family into 4 subfamilies (Planchonioideae, Foetidioideae, Napoleonaeoideae, and the Lecythidoideae) as was done by Niedenzu in 1892. Walker and Doyle (1975) comment on the different positions of Lecythidaceae in the Cronquist and Takhtajan systems and indicate that pollen does not help answer the problem.

Preliminary evidence from cytology tends also to support the separation of the Lecythidaceae from the Myrtaceae. The subfamily Leptospermoideae of the Myrtaceae has a constant number of 2« = 22 while the subfamily Myr-toideae has 2n numbers ranging from 22-28 (Atchison, 1947). The known chromosome numbers also support recognition of at least 3 of Niedenzu's (1892) 4 subfamilies. The Planchonioideae are x= 13 (Sobti and Singh, 1961; Roy and Jha, 1965, Mehra, 1972; Mangenot and Mangenot, 1962; Sarkar et al, 1976), the Napoleonaeoideae are x= 16 (Mangenot and Mangenot, 1957, 1962), and the Lecythidoideae are *=17 (Mangenot and Mangenot, 1958, 1962; Kowal et al, 1977). There are no counts from the Foetidioideae. Raven (1975) has treated the three subfamilies as three families based on their constantly different base numbers. Kowal et al (1977) concluded that chromosome data do not help place the Lecythidaceae sensu lato in any definite order of the angiosperms.

Hegnauer (1966) concluded from phytochemistry that the Lecythidaceae are close to the Myrtaceae. He does add, however, that for a more exact phytochemical comparison of the family there have been too few observations. Kubitzki, of the University of Hamburg, has begun a more detailed analysis of the phytochemistry of the family but has not yet published any results.

Most modern phylogenists treat the Lecythidaceae as a single family which includes the Barringtoniaceae and Asteranthaceae (Hutchinson, 1959; Payens, 1967; Thorne, 1968; Cronquist, 1968; Takhtajan, 1969; Stebbins, 1974). However, Hutchinson (1969, 1973) later separated the group into the 3 families recognized by Knuth, and Airy-Shaw (1973) treated all four subfamilies of Niedenzu (1892) as families and also placed Asteranthos in a family of its own. In his monograph of Barringtonia Payens (1967) suggests that:

Whatever subdivision to the Lecythidaceae should be given, there is in my opinion no argument to recognize more than one family, as the members are too intricately, and partly reticulately, knit together and furthermore have too much intrinsic structural characters in common.

There is, however, no agreement as to the position of the family among the Dicotyledons. Hutchinson (1959) and Takhtajan (1969) leave the family in the Myrtales, while Thorne (1968, 1976) places it in the Theales, and Cronquist (1968) in the Lecythidales, putting it somewhere between the Theales and Malvales. The large order Theales of Thorne (1976) includes the Lecythidineae as a suborder with one family Lecythidaceae which is divided into three subfamilies (Planchonioideae, Lecythidoideae and Napoleonaeoideae (including Asteranthos)). Thorne relates the Lecythidaceae to the Theales on account of their numerous stamens, showy imbricate petals, and centrifugal stamens. He

Table I.

Comparison of the differences between the Lecythidaceae and Myrtaceae

Character

Lecythidaceae

Myrtaceae

References

Flowers symmetry anthers stamen development actinomorphic or zygomorphic usually basifixed centrifugal actinomorphic usually versatile centripetal

Lawrence (1951) Lawrence (1951)

Thompson (1921, 1927), Cronquist (1968), Leins (1972), Thorne (1976)

Leaves arrangement margins stipules pellucid dots alternate often serrulate-serrate minute or absent absent usually opposite entire absent present

Lindley (1853), Thorne (1976) Lindley (1853)

Pittier (1927), Wçberling (1957), Lawrence (1951), Payens (1967) Lindley (1853)

Stem secrectory cavities internal phloem cortical bundles vestured pitting absent absent present absent present present absent present

Costantin and Dufour (1885) Costantin and Dufour (1885), Thorne (1976) Costantin and Dufour (1885), Lignier (1890) Thorne (1976)

Wood pores fiber pits parenchyma

Embryology nucellus integuments

Chromosomes number mostly solitary distinctly bordered paratracheal or diffuse scanty thick, with vascular tissue, fused mostly in multiples Diehl(1935)

simple or indistinctly bordered Diehl (1935) distinctly metatracheal Diehl (1935)

abundant

2 cells thick, without vascular tissue, separate

Mauritzon (1939) Mauritzon (1939)

n = 13 for the Planchonioideae, n = 11 for the Leptospermoideae, Atchison (1947), Banerjee (1950), Roy and Jha

16 for the Napoleonaeoideae n — 11-14 for the Myrtaceae (1965), Kowalet al (1977) and n= 17 for the Lecythidodeae

CO I"

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