Flora of New Zealand Series

Fls axillary, us. in terminal racemes or spikes, sts solitary. Calyx campanulate, 4-lobed, clefts even or uneven. Corolla-tube funnelform, short or much-elongated, ± pilose without; limb 2-lipped, upper lip concave, shortly 2-lobed, lower lip 3-lobed, spreading. Stamens 4, didynamous, inserted at throat of corolla; anthers cohering by margins, us. carried laterally by curvature of filaments, rarely free and erect, cells us. marginally hairy, equally or unequally awned at base. Style slender, stigma ± clavate to capitate, sts imperfectly 2-lobed. Fr. a loculicidal laterally compressed capsule, rarely indehiscent; seeds 1-(, testa whitish and furrowed. Annual to perennial semi-parasitic herbs or subshrubs with opp. lvs. Genus of c. 100 spp. widespread in temperate regions of both hemi-spheres, the N.Z. spp. endemic.

SYNOPSIS

• A.
• • Plant perennial with stout woody stock or slender, rooting, prostrate, woody stems but lfy branches erect without adventitious roots
  • 1.
  • • Plant lowland to subalpine, in lowlands a subshrub with much-branched infl. and small bracts:
    • 1. cuneata
  • 2.
  • • Plant always subalpine, never a subshrub, infl. always a simple raceme or spike with lflike bracts
    • (a)
    • • Calyx glab. or nearly so, clefts us. uneven:
      • 2. monroi, 3. laingii, 4. drucei
    • (b)
    • • Calyx white-pubescent and/or glandular-hairy, clefts not markedly uneven:
      • 5. revoluta, 6. townsonii, 7. petriei
• B.
• • Plant annual, stems never woody or rooting but prostrate lfy branches sts with adventitious roots
  • 1.
  • • Lvs of ovate order, crenate or toothed; branches erect, never rooting:
    • 8. cockayniana, 9. zelandica, 10. australis, 11. cheesemanii
  • 2.
  • • Lvs either deeply divided into linear segs or of lanceolate order and entire; branches mostly decumbent or prostrate, sts rooting
    • (a)
    • • Lvs deeply divided into linear segs; branches erect or decumbent, sts rooting at nodes:
      • 12. dyeri, 13. repens
    • (b)
    • • Lvs linear-lanceolate, entire; branches prostrate, copiously rooting at nodes:
      • 14. integrifolia
    • (c)
    • • Lvs of lanceolate order, entire or with 2 narrow teeth; branches prostrate but never rooting:
      • 15. disperma

Several growth-forms are represented in the N.Z. spp. and annual or perennial habit seems a valuable primary distinction, though the actual life-span of the spp. which appear to be at least potentially perennial is not known. Lvs are rather succulent when fresh and us. very brittle when dry; in all spp. there are patches of minute brown glands between the veins on the undersurface. Except in E. cuneata the floral lvs or bracts are little differentiated from the vegetative lvs and the terminal racemes or spikes are not clearly defined; in the annual spp. often all but the lowest 1-2 pairs of lvs subtend fls and the floral lvs are the largest and most highly developed. In the calyx the anterior and posterior clefts are often slightly longer than the lateral, but in some spp. they are regularly markedly longer. Fl.-colour is given simply as "white" for all spp. except E. cockayniana, although us. in fact the outside of the tube is yellow, there is a yellow patch on the inside of the throat and the lobes may be veined with purple. Size, colour and appendages of the anthers provide good taxonomic characters; awns may be of equal length on all 8 cells or long on the lower cells of the posterior (lower) pair of anthers and short of absent on the other 6 cells. Capsules are poorly known in some of the rarer spp.; particularly in E. dyeri, E. repens, E. integrifolia and E. disperma information is required about dehiscence (if any) and number of seeds.

Anther-awns and lf-shape formed the basis of Wettstein's geographic subdivisions of the genus (Mon. Gatt. Euphrasia 1896); he recognized only 7 spp. from N.Z. but erroneously placed them all, together with the Australian spp., in subsection Australes -- anthers pilose, subequally mucronate. Du Rietz (Svensk bot. Tidskr. 25, 1931) reviewed (526-539) the inter-relationships and classification of the Pacific spp.; he also discussed (108-125), with illustrations, the relation of Siphonidium J.B. Armst. to the N.Z. Euphrasia spp. and concluded: "There is such a gradual transition between Siphonidium and Euphrasia sens. strict. that it is not possible at our present state of knowledge to retain Siphonidium as a separate genus . . . . it seems even doubtful whether Siphonidium should be retained as a subgenus or a section." This treatment is here accepted, though E. disperma remains anomalous not only in the long corolla-tube but also in the free erect anthers and peculiar calyx and capsule. As noted by Du Rietz a connecting group is formed by those spp. of Euphrasia, especially E. dyeri and E. repens, with partly elongated corolla-tubes and reduced numbers of ovules. Should these spp. be shown to have indehiscent capsules there might be justification for restoring Hooker's subgenus Anagosperma, originally founded to contain E. disperma and E. repens on the basis of their 1-ovuled locules; if E. disperma is the only sp. with an indehiscent capsule its position is isolated.

Fig. 34. EUPHRASIA. Leaves: hairs not shown. © All rights reserved. [Image: 4X1I]