IAWA Bulletin n.s., Vol. 3 (1), 1982 45

THE WOOD STRUCTURE OF COURATARI AUBL. AND COUROUPlTA AUBL. (LECYTHIDACEAE)

by

H.G. Richter Institut fUr Holzbiologie und Holzschutz, Bundesforschungsanstalt fUr Forst- und Holzwirtschaft, Leuschnerstrasse 91, 2050 Hamburg 80, Federal Republic of Germany

Summary Woods of the genera Couratari Aubl. and belong to the family of Lecythidaceac invol­ Couroupita Aubl. (Lecythidaceae) correspond ving two of its exclusively neotropical genera: in appearance and are nearly indistinguishable Couratari Aubl. and Couroupita Aubl. macroscopically. However, microstructural fea­ Existing information on secondary xylem tures such as parenchyma distribution as well differentiation of Couratari and Couroupita is as type and configuration of inorganic contents rather scanty and must be inferred from gener­ (silica, Ca-oxalate crystals) can be employed al family (Diehl, 1935) or individual species de­ for safely separating the two genera wood ana­ scriptions (e.g. Dechamps, 1979; Richter, 1969 tomically. The significance of these features is and others); no direct comparison referring to tested in terms of diagnostic value and their wood structural data of the two genera is avail­ taxonomic implications discussed through pro­ able. Ter Welle (1980, personal communica­ jection into the neotropical subfamily Lecythi­ tion) has indicated that the only means of dis­ doideae and further into Old World Lecythida­ tinguishing Couratari from Couroupita wood ceae. As a result a subdivision of Lecythidoi­ anatomically is the presence of silica in the for­ deae into two groups is suggested: one com­ mer and lack, respectively, in the latter. The prising Couratari and the structurally similar following wood structural analysis is geared to­ genera Allantoma, Bertholletia, Corytophora, wards establishing reliable criteria for generic Eschweilera and Lecythis sharing a character differentiation. Subsequently the possible combination unique in Lecythidaceae; the taxonomic implications of such distinguishing other comprising Couroupita, Grias and Gusta­ features are discussed. via with certain affinities towards Old World Macroscopically the woods of both genera Planchonioideae. Cariniana, although structur­ are indistinguishable for all practical purposes; ally close to Couratari and allied genera, is ac­ hence it is not surprising to find them lumped corded an intermediate position. The timbers together in one group of commercial timbers. of Couratari and Couroupita lend themselves Beside the similar appearance of the woods, for a sImilar range of end use categories such as both genera have a number of other character­ utility plywood, interior construction, furni­ istics in common: ture parts etc. They may, for all practical pur­ 1. Their distribution is exclusively neotropical poses, be combined in one group of commer­ and restricted to the northern part of South cial timbers to be used eventually as SUbstitutes America, encompassing the Amazone Basin, for such well known medium density woods as the Guyanas, and radiating north into Cen­ Ramin, Virola and others. tral America, south to central and eastern Brazil. The centre of distribution of Coura­ In troduction tari lies in the Guyana region, that of Cou­ During the past years occasional shipments roup ita further southwest in central Amazo­ of a light coloured medium density wood from nia. South America appeared on the German mar­ 2. The trees of both genera are among the larg­ ket. Invariably the wood was imported on a est and best formed in the American tropical trial basis as veneer, furniture parts, broom forest reaching up to 35 metres in height and sticks etc. It was introduced mostly from Brazil, 0.9 to 1.2 metres at d.b.h., with straight Peru and the Guyanas under such misleading boles up to 20 metres; they are relatively fantasy names as 'Brazilian cherry' or 'Corina', scarce and widely scattered. the latter a US-trade name normally applied to 3. Both genera supply a medium density wood the west African wood 'Limb a' of Terminalia (0.40-0.60 g/cm3 for Couroupita, 0.50- superba, Combretaceae. Repeated microscopic 0.72 g/cm3 for Couratari) which is reported analyses revealed that all investigated samples to be firm, tough and strong (Record & Hess,

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Table I. - Couratari Aubl.: wood specimens examined (species identification according to Mori & Prance, unpub!.; Prance, pers. comm.)

RBHw Species Collector number Origin Original xylarium number number and identification (if deviating)

6269 C. exigua Miers* Trinidad (= Cariniana pyriformis) 750 C. guianensis Aubl. Gerhard 46 Surinam 6570 ibid. (Herb. Utrecht) Surinam Uw 2009, C. puIchra Sandw. 13632 ibid. Colombia C. puIchra Sandw. 16334 ibid. Stahel49 Surinam Uw49 16833 ibid. Stahel58 Surinam Uw 58, C. puIchra Sandw. 16836 ibid. Surinam BBSw 7, C. puIchra Sandw. 16838 ibid. Venezuela MERwD 299, C. puIchra Sandw. 17104 ibid. Brazil CTFw5660= SJRw45538, C. puIchra Sandw. 17105 ibid. Gossin 42 Fr. Guyana CTFw 20674 17106 ibid. Breteler 5007 Venezuela CTFw 17146, C. puIchra Sandw. 17124 ibid. De Bruyn 1533 Venezuela Uw 14491, C. panamensis Standley 17125 ibid. P.H. Allen s.n. Costa Rica Uw 10374 = USw 30147, C. panamensis Standley ibid.** Fr. Guyana CTFw 16636, C. puIchra Sandw. ibid.** Fr. Guyana CTFw 16645, C. puIchra Sandw. 17110 C. macrosperma A.C.Smith Krukoff 6451 Brazil CTFw 18231 10164 C. multiflora (J .E.Smith) (Herb. Utrecht) Surinam Uw 1652, Eyma C. fagifolia (Miq.) Eyma 10908 ibid. Rio de Janeiro 2405 Brazil C. coriacea Mart. ex Berg 16832 ibid. Stahel44 Surinam Uw44 16837 ibid. Venezuela MERwPG-24 16839 ibid. Surinam BBSw,6, C. fagifolia (Miq.) Eyma 17111 ibid. Stahel58a Surinam Uw 58a = CTFw 4438 ibid. ** Fr. Guyana CTFw 16780, C. fagifolia (Miq.) Eyma ibid.** Bafog 84 M Fr. Guyana CTFw 7726, C. fagifolia (Miq.) Eyma 17108 C. oblongifolia Ducke & Brazil CTFw 5662 = SJRw 45540 Knuth 16835 C. stellata A.C.Smith Stahel 137a Surinam Uw 137a 16840 ibid. Surinam BBSw b-19 16841 Couratari sp. Splitgerber 727 Surinam 3641 cf. Couratari Fr. Guyana

* Original identification erroneous, transferred to Cariniana pyriformis. **Only slides available for microscopic examination.

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Table 2. - Couroupita Aubl.: wood specimens examined (species identification according to Mori & Prance, unpubl.; Prance, pers. comm.)

RBHw Species Collector number Origin Original xylarium number number and identification (if deviating)

2871 C. guianensis Aubl. Tessmann 4777 East.Peru C. peruviana Berg 16333 ibid. (I 363/XII, Utrecht) Surinam Uw 1459 16335 ibid. StaheIIOO/X Surinam Uw 100 ibid. * Ortega 267 Ecuador CTFw 22102 17113 C. nicaraguarensis DC. Panama CTFw 14062 = Uw 7169 = USw 729, C. darienensis Pittier 17112 C. subsessilis Guttierrez 209 Peru CTFw 17556 = MADw 23373, C. amazonica Knuth 17114 ibid. Rhone-Poulenc s.n. Brazil CTFw 26027, C. amazonica Knuth 17129 ibid. Krukoff 8066 Brazil Uw 16248, C. amazonica Knuth 13496** Couroupita sp. Brazil Couratari guianensis Aubl. 17109** Couroupita sp. Presdesur 1002AM Ecuador CTFw 21280, Couratari sp.

* Only slide available for examination. ** Samples originally identified as Couratari but transferred to Couroupita based on structural evi­ dence.

1949); rather coarse textured with a straight gy of inorganic inclusions were observed in grain, easy to work except for a notable dul­ bleached sections in clove oil (Ter Welle, 1976). ling effect on cutting edges for species of Terminology and measurements are in accor­ Couratari, heartwood reported to be non dance with the standards developed by the In­ durable (Couroupita) to at the most modera­ ternational Association of Wood Anatomists tely durable (Couratari). (1964). Numerical values referred to in the de­ On the other hand. exomorphic characters scriptions reflect generic means unless specified offer ample ground for distinguishing Couratari otherwise. Photomicrographs were taken with a from Couroupita based mostly on flowers, fruit Zeiss-UItraphot or an Autoscan (ETEC) scan­ and seeds: ning electron microscope. I. Cauliflory in Couroupita vs. terminal posi­ tion of inflorescence in Couratari species. Wood Anatomical Descriptions 2. Fruit round (,Cannon-ball-tree') and indehis­ cent in Couroupita vs. cylindrical (pipe­ Couratari Aubl. (Figs. 1-6,13-15) shaped) and dehiscent in Couratari. Growth rings faint to distinct. - Vessels dif­ 3. Seeds without wings (animal dispersal) in fuse, 2-3/mm2 (up to 5 in C. guianensis), soli­ Couroupita vs. winged seeds (wind dispersal) tary and in radial multiples of 2-6 in varying in Couratari. proportions; mostly oval in transverse section, According to Prance and Mori (1980) both wall thickness thin to medium (8-12 !Lm), tan­ Couratari and Couroupita are relatively small gential diameter (130-)150-230( -330) !Lm. taxonomic units represented by 15 and 4 spe­ Perforations simple in horizontal to oblique cies, respectively. end walls. Intervessel pits alternate, not crowd­ ed, mostly circular to weakly polygonal, (7-) Material and Methods 8-1 O( -12) !Lm in diameter; apertures slit-like The study is based on 28 specimens of Cou­ and included. Tyloses present in most speci­ ratari (see Table I) and 10 specimens of Cou­ mens, infrequent and thin-walled. No gum de­ roup ita (see Table 2) representing 5 and 3 spe­ posits observed. - Fibres libriform, thin to fair­ cies, respectively. Microscopic slides were pre­ ly thick-walled (c. stellata) with small (c. 3 !Lm) pared from all samples following common labo­ bordered pits in radial and tangential walls. ratory procedures. Distribution and morpholo- More or less aligned radially on transverse sec-

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tion, non-septate. No contents observed. - Pa­ guianensis), maximum diameters reaching 250, renchyma predominantly apotracheal, banded 280 and 330/lm respectively. Perforations sim­ as fine, mostly uniseriate to sometimes biseriate ple in horizontal to oblique end walls. Interves­ (including some marginal) lines forming a con­ sel pits alternate, not crowded; uniformly cir­ spicuous scalariform pattern with broader rays; cular, (9-) I 0-12 /lm in diameter; apertures bands closely and regularly spaced (8-12/mm) slit-like and included. Tyloses present, general­ except in proximity of growth ring limits where ly sparse and thin-walled; abundant and thick­ spacing becomes rather variable. Bands fewer walled in C nicaraguarensis including large and wider (4-8/mm, 2-3-seriate) in C oblon­ rhombohedric crystals. No gum deposits ob­ gifolia. Individual cells considerably extended served. - Fibres libriform, generally thin-walled vertically with diameters about equal to that of with small (2-3 /lm) bordered pits in radial fibres, but with much thinner walls which aids and tangential walls. More or less radially align­ differentiation on transverse section. Paren­ ed on transverse section, non-septate. No con­ chyma strands of (3-)4-6( -8) cells, frequent­ tents observed. - Parenchyma predominantly ly accompanied by vertical strings of up to 100 apotracheal, finely reticulate as diffuse, regular individual cells each containing one small rhom­ to oblique uniseriate (rarely biseriate) lines be­ bohedric crystal (Ca-oxalate) embedded in the tween rays; spacing even and close (l0-16/mm) unilaterally thickened cell wall; crystalliferous becoming uneven at certain intervals indicating strands located invariably on the adaxial side of growth ring limits. Cells considerably extended parenchyma with the concentration of second­ vertically, diameter and wall thickness about ary wall thickening towards the side adjacent equal to that of fibres (difficult to differenti­ to the fibres, frequently leaving a large cavity ate on cross section). Strands of (3-)4-6( -8) on the opposite side. Para tracheal parenchyma cells. All specimens with occasional to abun­ sparingly developed as individual strands con­ dant chambered crystalliferous cells forming in­ tiguous to vessels, non-crystalliferous. All pa­ tegrated parts of parenchyma strands, and each renchyma cell walls abundantly pitted; pits al­ containing from 2 to 8 large rhombohedric most exclusively confined to radial walls giving crystals (Ca-oxalate). Paratracheal parenchyma the impression of a sieve-like pattern (radial sparingly developed as individual strands adja­ section). Yellowish to brown gum deposits fre­ cent to vessels, non-crystalliferous. All paren­ quently present. - Rays variable in width: pre­ chyma cells abundantly pitted almost exclusi­ dominantly 3- or 4-seriate in C guianensis, 2- vely in radial walls, suggesting a sieve-like pat­ or 3-seriate in the remaining species; composed tern. Light brown to yellowish gum deposits of procumbent cells occasionally with one mar­ occasionally present. - Rays variable in width: ginal row of square cells. Vessel-ray pitting 2- to 3-seriate in C guianensis, 3-seriate in C similar to intervascular pit pairs in outline and subsessilis and 3- to 4-seriate in C nicaragua­ size. Maximum ray height generally less than rensis; composed of procumbent cells occasion­ I mm, that of vertically fused rays up to 1.5 ally with one marginal row of squarish to up­ mm. Globular to irregular silica grains with right cells. Vessel-ray pits similar to intervas­ granular surface sparingly to abundantly devel­ cular pit pairs in form and size, intermittently oped, mostly embedded in yellowish to brown large and gash-like. Rays coarse-textured and gum deposits. No crystals observed. All ray frequently fused vertically, the latter reaching cells abundantly pitted. up to 2 mm height. Gum deposits rare, crys­ tals and silica not observed. Courol/pita Aubl. (Figs. 7--11,16-18) Growth rings for the most part indistinct. - From the foregoing descriptions it becomes Vessels diffuse, 1 to 3/mm2 (up to 5 in C guia­ evident that the woods of both Couratari and Ilellsis, up to 7 in C nicaraguarensis); solitary Couroupita resemble each other very much in and in radial multiples of 1 to 5 in variable pro­ terms of general structure and appearance. portions, including some narrow vessels; mostly There are, however, few microstructural details oval in transverse section and thin-walled; aver­ of the secondary xylem which in combination age tangential diameter from 160 (C subsessi­ leave no doubt about their generic identity lis), 190 (C nicaraguarensis) to 120 /lm (C (Table 3).

Fig. 1-6. Couratari Aubl. -- 1-3: Couratari guianensis. Transverse, tangential and radial sections. -- 4 & 5: Couratari sp. Overall view and close-up of crystal strings, unilaterally contiguous to non­ crystalliferous axial parenchyma strands (radial section). -- 6: Couratari macrosperma. Silica grains in ray cells.

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Table 3. - Microstructural differences in the secondary xylem of Couratari Aubl. and Couroupita Aubl.

Feature Couratari Couroupita

Axial Predominantly continuous fine tangential Diffusely reticulate in short tangen­ parenchyma bands (1-2-seriate); easily differentiated tial, often oblique lines between rays; from alternating fibre layers (transverse hardly distinguishable from alterna­ section, Fig. 1). ting fibre layers (transverse section, Fig. 7).

Ca-oxalate In vertically extended strings of up to Chambered crystalliferous cells inte­ crystals 100 individual cells accompanying paren­ grated in and dimensionally identical chyma strands; located at the adaxial to non-crystalliferous cells of paren­ side; crystals embedded in secondary wall chyma strands; cell walls regularly thickening contiguous to fibre side. No pitted (Figs. 10, 11, 12, 16, 17, 18). pits or other markings in cell walls ob­ served (Figs. 4, 5, 13, 14, 15).

Silica Globular to irregular grains, sparse to Absent. abundant in rays, occasionally in axial parenchyma (Fig. 6).

Taxonomic considerations classification first suggested by Niedenzu (1892, According to the various systematic treat­ see Table 4) one finds all neotropical genera ex­ ments Couratari and Couroupita are - among cept Asteranthos assembled in the subfamily other genera - usually placed jointly in a single Lecythidoideae with no further formal subdivi­ taxonomic unit either at the family, subfamily, sion proposed. tribal or subtriballevel (for comparison of clas­ With regard to secondary xylem anatomy sifications see Prance & Mori, 1980). The neo­ such an unstratified assembly appears justified tropical genera Grias and Gustavia were main­ only in the most general terms of structural ar­ tained separately by earlier botanists (e.g. Lind­ chitecture of the taxa concerned. Specific de­ ley, 1846 - Barringtoniaceae; LeMaout & De­ tails of structure and inorganic contents suggest caisne, 1873 - subtribe Barringtonieae). More the possible formation of at least two distinct recently, taxonomists jointly assembled all neo­ groups within Lecythidoideae (sensu Niedenzu, tropical genera except Asteranthos in a single 1892): taxonomic unit (Miers, 1874; Niedenzu, 1892; I. Allantoma, Bertholletia, Corytophora, Cou­ Knuth, 1939; Pichon, 1945;Airy Shaw, 1973). ratari, Eschweilera and Lecythis, all sharing The separate status accorded A steranthos (Nie­ in a similar manner the character combina­ denzu, 1892 - Napoleonaeoideae; Airy Shaw, tion described above for Couratari. This set 1973 - Asteranthaceae) is readily reflected in of anatomical features is unique within Le­ its particular wood anatomy characterised, cythidaceae as a whole to an extent that among other criteria, by multiple (scalariform could possibly allow for a distinct status of to reticulate) vessel perforations, scalariform this group within the family. In fact, the cor­ vessel-ray pitting and strongly heterogeneous responding woods are so similar that differ­ rays. On the other hand, vessel perforations are entiation by means of microstructural crite­ simple, vessel-ray pitting is non-scalariform, ria might remain inconclusive and must more and wood rays tend to homogeneity in the re­ often than not be aided by secondary fea­ maining neotropical genera. Following Prance tures such as heartwood colour and specific and Mori (1980) in provisionally adopting the gravity.

Fig. 7-12. Couroupita Aubl. - 7-9: Couroupita subsessilis. Transverse, tangential and radial sec­ tion. - 10: Couroupita sp. (radial section) and II: Couroupita subsessilis (tangential section): chambered crystalliferous celkintegrated in axial parenchyma strands. - 12: Couroupita sp. as in Fig. 10, close-up (radial section).

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Table 4. - Arrangement of genera of Lecythi­ etc.) both quantitatively and qualitatively. daceae by subfamily (extracted from Prance & Cariniana might for all practical purposes be Mori, 1980). included in the Couratari-group (viz. paren­ chyma distribution, silica content). With re­ Subfamily Genus Number gard to crystalline inclusions, however, Cari­ of niana occupies an interesting intermediate species position by combining the characters of both Couratari and Couroupita. Planchonioideae Abdulmajidia* 2 When scrutinising the Old World representa­ Barringtonia 40 tives of Lecythidaceae for similar character com­ Careya 4 binations as employed for the definition of the Chydenanthus 2 two above groups the following picture evolves: Petersianthus* * 2 Parenchyma - The diffusely reticulate pattern Planchonia 5 is predominant in genera of the subfamily Plan­ Foetidioideae Foetidia*** 5 chonioideae (except the typically paratracheal Napoleonaeoideae Asteranthos I and/or metatracheal banded parenchyma in Crateranthus 3 Petersianthus, Barringtonia, Chydenanthus), Napoleonaea 8 and in Napoleonaeoideae. The regular apotra­ Lecythidoideae Allantoma I cheal banded condition found in the Couratari Bertholletia I group and in Cariniana is unparalleled in the re­ Cariniana 15 maining Lecythidaceae. Corytophora I Crystals - Chambered crystalliferous cells as Couratari 15 integrated parts of parenchyma strands are also Couroupita 4 common in Asteranthos (provisionally placed Eschweilera c.100 in Napoleonaeoideae) and Foetidia (Foetidioi­ Grias 6 deae), some individual strands also being dif­ Gustavia 41 fuse in the latter (Diehl, 1935). Crystals are Lecythis c. 25 rather large in Foetidia and appear to be em­ bedded in somewhat irregularly thickened cell * No wood specimens available for study. walls. Solitary crystals in ray cells as observed ** Disjunct distribution: I species in West Afri­ in Grias and Gustavia and reported for Courou­ ca, another in the Philippines. pita (Diehl, 1935) occur regularly in Plan chon­ *** Disjunct distribution: Pemba Is. and Mada­ ioideae and Napoleonaea, rarely in Asteranthos; gascar, India and Malaysia (from the latter their presence in Cariniana as reported by Diehl region no specimens were available for (1935) could not be confirmed with the mate­ study). rial at hand for the present investigation. ------Silica - Small to medium-sized grains are com­ mon only in one of the two species of Petersi­ 2. Couroupita, Grias and Gustavia, all sharing anthus (P. quadrialatus from the Philippine Is­ in a similar way the parenchyma distribution, lands), and in Malagasy representatives of Foe­ crystal configuration and lack of silica as de­ tidia. In P. quadrialatus grains are rather com­ scribed above for Couroupita. Contrary to pact, of medium size and evenly distributed in what applies to Couratari and allied genera, ray and axial parenchyma. In specimens of the secondary xylem structure of these three Foetidia silica appears as small aggregates of genera is distinct and may easily be separated tiny granules rather than compact grains, lo­ by means of other characters (vessels, rays, cated predominantly in rays.

Fig. 13-18. Scanning electron micrographs (scale 10 /lm). -- 13: Couratari guianensis. String of crystalliferous cells (arrow) adjacent to uniseriate parenchyma strand; note individual crystal torn from original site in thickened cell wall. -- 14: Couratari guianensis. As in Fig. 13, close-up; note unilaterally thickened cell wall (w) on fibre (f) side and open spaces next to parenchyma (p). -­ IS: Couratari guianensis. Cavities left by removal of individual crystals from enclosing cell wall; note thickened cell wall (w) towards fibre (f) and thin membrane towards parenchyma (p). -- 16: Couroupita subsessilis. Parenchyma strands with integrated chambered crystalliferous cells (arrows). -- 17: Couroupita subsessilis. Chambered crystalliferous (c) cell in biseriate parenchyma strand; note sieve-like pattern in pitted cell wall (arrow). -- 18: Couroupita guianensis. Close-up view of chambered crystalliferous (c) cell with crystals removed from upper two compartments.

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Conclusions The superficial resemblance of Couratari and yond the scope of generic distinction between Couroupita timbers is betrayed by constant mi­ Couratari and Couroupita. crostructural differences in parenchyma distri­ With regard to wood utilisation neither Cou­ bution and type as well as arrangement of inor­ ratari nor Couroupita timbers need to be sub­ ganic contents. A survey of other lecythida­ jected to species differentiation. Structural uni­ ceous genera reveals that the structural pattern formity and similarity in physical/mechanical of Couratari is repeated exclusively in the neo­ properties in either genus can be assumed to al­ tropical genera Allantoma, Bertholletia, Cory­ low for pooling individual species into commer­ tophora, Eschweilera and Lecythis while that cial groups of timber. When considering the of Couroupita corresponds more closely to relative structural and technical variation with­ Grias, Gustavia and to the Old World Plancho­ in successful commercial timber groups like the nioideae. Cariniana occupies an intermediate Southeast Asian 'Red Meranti', the Mahagonies position by combining the characteristic crystal and others, Couratari and Couroupita might configurations of either group. Distributional well be combined under one group of commer­ pattern and particular arrangements of inorgan­ cial timbers without jeopardising their adequate ic inclusions in wood have proven their diag­ utilisation. Within such an entity consideration nostic value and taxonomic significance repeat­ will have to be given to differences in machin­ edly at specific, generic and family levels. The ing properties due to the silica content in Cou­ evidence presented above and experience gath­ ratari species and to specific gravity variation ered from similar endeavours with other plant within and between the generic units. In general families (e.g. Gottwald & Parameswaran, 1966; terms timbers of this group appear to be most Richter, 1980) give rise to the assumption that suitable for plywood manufacturing (utility the neotropicallecythidaceous genera assembled grades), interior construction, mouldings, panel­ in the subfamily Lecythidoideae might require ling, furniture parts etc. According to their some further stratification beyond the formal properties they might eventually serve as sub­ level proposed. In fact, a possible indication of stitutes for a number of sought-after commer­ such a subdivision might be derived from Nie­ cial timbers: the lighter grades for the African denzu's treatment of Lecythidaceae: apparent­ Oukume or the South American Virola, the ly based mainly on seed characters the genera heavier grades for the Southeast Asian Ramin Japarandiba (= Gustavia), Grias, Couroupita or the African Limba and Framire. and Lecythis are joined under a common head­ ing (denominated A) with Lecythis (subgroup References b) still separated from the other three genera Airy Shaw, H.K. 1973. In: J.C. Willis, A dictio­ (subgroup a). The second group (denominated nary of flowering plants and ferns. 8th Ed. B) includes Eschweilera, Berthol/etia, Cariniana, Cambridge Univ. Press, Cambridge. Cercophora (= Lecythis), Couratari and Allan­ Dechamps, R. 1979. Etude anatomiq ue des toma. Except for the rather unsatisfactory po­ bois d'Amerique du Sud. Vol. I. Acantha­ sition of Lecythis s.l. (Lecythis in group A, ceae~ Lecythidaceae. Annales Serie IN-8°, Cercophora in group B) this further division of Sciences Economiques No. 10. Mus. Royal Lecythidoideae corresponds rather well with the de I'Afrique Centrale, Tervuren, Belgium. evidence gathered from wood anatomical data. Diehl, G.A. 1935. A study of Lecythidaceae. Diversity of the secondary xylem of Lecythi­ Trop. Woods 43: 1~15. daceae, particularly within the subfamily Lecy­ Gottwald, H. & N. Parameswaran. 1966. Das thidoideae comprising all neotropical genera sekundare Xylem der Familie Dipterocar­ but Asteranthos, might therefore prove more paceae, anatomische Untersuchungen zur helpful for classification purposes than had Taxonomie und Phylogenie. Bot. J ahrb. been recognised so far. Presence and absence, 85: 41O~508. respectively, of crystal chains have been accor­ IAWA Committee on Nomenclature. 1964. Mul­ ded some significance (Prance & Mori, 1980), tilingual glossary of terms used in wood however without giving a complete picture of anatomy. Konkordia, Winterthur. their distribution (Asteranthos has crystal chains Knuth, R. 1939. Lecythidaceae. In: A. Engler, but is listed under 'without crystal chains' ~ Pflanzenreich VI, 219a: I ~ 146. Napoleonaeoideae), and without giving heed to LeMaout, E, & J. Decaisne. 1873. General sys­ the constant morphological and configurational tem of botany. Longmans Green, London. differences of crystalline contents as described Lindley, J. 1846. The vegetable kingdom: 716~ above. Such diversity including that of paren­ 730. London. chyma distribution and occurrence of silica Miers, J. 1874. On the Lecythida<:cae. Trans. might merit future taxonomic recognition bc- Linn. Soc. London 30: 157~318.

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Niedenzu, F. 1892. Lecythidaceae. In: A. Eng­ -- 1980. On the occurrence, morphology ler & K. Prantl, Die naturlichen Pflanzen­ and taxonomic implications of crystalline familien 3 (7): 26-41. and siliceous inclusions in the secondary Pichon, M. 1945. Le genre Combretodendron xylem of Lauraceae and related families. et les Lecythidacees. Not. Syst. Paris 12: Wood Sci. Technol. 14: 35-44. 192-197. Welle, B.J.H. ter. 1976. Silica grains in woody Prance, G.T. & S. Mori. 1980. Lecythidaceae. plants of the Neotropics especially Suri­ Part I. Flora Neotropica, Monograph No. nam. In: Wood structure in biological and 21. New York Bot. Garden, New York. technological research (eds. P. Baas, A.J. Record, S.J. & R. Hess. 1949. Timbers of the Bolton & D.M. Catling). Leiden Bot. Ser. New World. Yale Univ. Press, New Haven. 3: 107-142. Leiden Univ. Press, The Richter, H.G. 1969. General, macro and micro­ Hague. scopic characteristics of 113 Panamanian species. F AOjUNDOjSF 234, Invent. For. Demonstr., San Jose, Costa Rica.

REVIEW

Xylem Cell Development. J. R. Barnett (ed.), ding an interesting discussion of factors gover­ 307 pp., illus., 1981. Castle House Publ., Turn­ ning lignification. J .H. Dodds discusses the role bridge Wells, Kent, U.K. Price £ 19.00 (hard of the cell cycle and cell division in xylem dif­ cover). ferentiation. P.B. Gahan treats biochemical This well-produced book contains ten chap­ changes of especially nucleic acids and proteins. ters on various aspects of xylem development R.A. Savidge and P.F. Wareing cover the exten­ and a general introduction by R.D. Preston. sive and complex field of plant-growth regula­ For each topic specialists were invited to re­ tors in the differentiation of vascular elements, view the state of knowledge and - more signifi­ and admit in their conclusion that information cantly - to give a synthesis of current under­ gathered so far seems to raise more problems standing. This approach proves to be very re­ than it solves. M.P. Denne and R.S. Dodd, on warding for the well-defined theme of xylem the other hand, suggest that in spite of the cell development (excluding secondary changes). complexity of interacting processes, trends can Not only for the super-specialist, but also for be perceived in the environmental control of anyone with a general interest in wood struc­ xylem differentiation, which may eventually ture, a fairly comprehensive and coherent pic­ be used in wood quality control in forestry. ture of xylem cell ontogeny emerges, which Spiral grain formation is the subject of a well­ makes this book a very valuable source for written paper by J.M. Harris. B.F. Wilson is the future reference. Selected chapters can also be author of the final chapter on development of recommended for post graduate teaching. growth strains and stresses in reaction wood. The first chapter by T.P. O'Brien discusses The present reviewer is certainly not quali­ primary xylem cell development in a stimula­ fied to give a critical assessment of the individ­ ting way. The editor, J.R. Barnett, covers simi­ ual contributions, but a high standard of q uali­ lar ground for the secondary xylem. A compar­ ty seems to be maintained throughout the ison of the research emphases and results for book. Too numerous printing errors in the both categories of xylem provide an interesting bibliographies are a· minor imperfection, COI11- and valuable complement. B.A. Meylan and pared with the wealth of information brought B.G. Butterfield give a comprehensive account together on this highly dynamic field of study of the partly elusive process of perforation plate in botany and wood science. differentiation in hardwoods. A.B. Wardrop deals with lignification and xylogenesis, inclu- I'il'll'l' Baas

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