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Current Research Bibliography Classification and Taxonomy Links
Some pictures currently stored/linked from "Land Plant On Line"   Text by D.L. Nickrent and K.S. Renzaglia. 
  • Anthoceros punctatus (A. agrestis). TEM showing channel thylakoids (arrowheads) and lack of grana and membranes, characteristics of hornwort chloroplasts. Inset shows a granum from Vicia faba chloroplast with curved end membranes which contrasts with that of hornworts. From Vaughn et al. (1992).
  • Anthoceros punctatus. Light micrograph showing dorsal schizogenous mucilage cavities. Photo by K. S. Renzaglia.
  • Anthoceros crispulus. Light micrograph showing antheridial cavity with 8 endogenous antheridia attached to the base. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. Light micrograph showing precocious endosporic spore germination within a capsule. Note the columella. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. SEM of ventral side of thallus showing mucilage clefts (pores) along midrib. These are the sites of entry of the endosymbiont Nostoc bacteria. Bar = x Ám. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. SEM of dorsal side of thallus showing antheridial cavities and sunken archegonia. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. SEM, enlarged view, showing single antheridium rupturing chamber roof. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. SEM, enlarged view, showing two rows of sunken archegonia, each with six rows of neck cells. The circular line surrounding each archegonium is the remnant of the mucilage plug. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Dendroceros tubercularis. TEM of chloroplast showing central pyrenoid (P) composed of irregularly-shaped subunits. Inset shows differential interference contrast image of one cell with a single plastid. Specimen from Japan provided by Dr. J. Hasagawa. From Vaughn et al. (1992).
  • Folioceros fusiformis. TEM of chloroplast showing details of pyrenoid and surrounding starch. From Vaughn et al. (1992).
  • Megaceros flagellaris. SEM of dehiscing sporophyte showing abundant sporogenous tissue. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Megaceros flagellaris. SEM showing spores amongst elongated pseudoelaters with spiral thickenings. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Megaceros aenigmaticus. TEM of the thallus epidermis showing large plastids with interspersed starch that lack a pyrenoid. Photo by K. S. Renzaglia.
  • Notothylas orbicularis. Color light micrograph showing longitudinal section of sporophyte with central columella and spores separated by pseudoelaters that extend from the columella to the epidermis. The spores, present as tetrads, contain abundant nutritive material (dark spots). Photo taken at 100X. Specimen from Cove Hollow, Illinois. Photo by K. S. Renzaglia.
  • Notothylas orbicularis. SEM of longitudinally-sectioned mature sporophyte showing spore tetrads and interspersed pseudoelaters. Note that the sporophyte is still enclosed within the involucre. Photo by K. S. Renzaglia.
  • Notothylas orbicularis. Color drawing of reconstruction of spermatozoid. Illustration by K. S. Renzaglia.
  • Notothylas temperata. TEM showing three of the four spores present in a tetrad. Note the cluster is still enclosed within the spore mother cell wall (thin outer line). Within the spores are storage proteins (dark circles) and storage lipids (grey circles). Each cell contains one chloroplast. Specimen from Japan provided by Dr. J. Hasagawa. Photo by K. S. Renzaglia.
  • Notothylas temperata. TEM of pyrenoid showing subunits with inclusions of stroma (S). Specimen from Japan provided by Dr. J. Hasagawa. From Vaughn et al. (1992).
  • Phaeoceros carolinianus. Color photo showing habit of plants with sporophytes. Buffalo Mt., Tennessee. Photo by K. S. Renzaglia.
  • Phaeoceros carolinianus. Habit of gametophyte with emerging young sporophytes. Photo by K. S. Renzaglia
  • Phaeoceros carolinianus. SEM of gametophyte thallus. Photo by Jim Thompson
  • Phaeoceros carolinianus. Light micrograph showing spore tetrads. 400X. Photo by Jim Thompson.
  • Phaeoceros carolinianus. SEM of spore showing distal face. Bar equals 10 Ám. Photo by Jim Thompson
  • Phaeoceros carolinianus. SEM of spore showing proximal face. Bar equals 10 Ám. Photo by Jim Thompson.
  • Phaeoceros carolinianus. SEM showing longitudinal view of opened sporophyte. The columella is surrounded by a sporogenous zone including spore tetrads and pseudoelaters. Photo by K. S. Renzaglia.
  • Phaeoceros carolinianus. SEM of two partial tetrads showing proximal spore surface with minimal ornamentation, distal highly ornamented spore surface and surrounding pseudoelaters. Photo by K. S. Renzaglia.
  • Phaeoceros carolinianus. SEM view of tetrad showing distal spore surfaces and remnant sporocyte wall. Photo by K. S. Renzaglia.
  • Phaeoceros laevis. Color light micrograph of a cross section of the hornwort sporophyte showing zonation. Internal to the single-layered epidermis is the assimilative zone with reddish, elongated chloroplasts. The central 16-celled (in section) columella is surrounded by sporogenous tissue. Taken at 100X. Photo by K. S. Renzaglia.
  • Phaeoceros laevis. Color light micrograph of a stomate from epidermis of a hornwort sporophyte. 400X. Specimen from Bastrop Texas. Photo by K. S. Renzaglia.
  • Phaeoceros laevis. TEM of sunken archegonium showing basal egg cell, ventral canal cell (VC), and four neck canal cells. From Vaughn et al. (1992).
  • Phaeoceros laevis. TEM of chloroplast showing details of the pyrenoid. Inset shows differential interference contrast image of one cell with a single plastid. From Vaughn et al. (1992).
  • Phaeoceros sp. Epidermal cells of a hornwort gametophyte stained with acid fuchsin to highlight the pyrenoid with the large, solitary, starch-laden chloroplasts. 400X. Photo by K. S. Renzaglia.
  • Phaeoceros carolinianus. Light micrograph showing unicellular ventral rhizoids. Note lack of internal differentiation of the thallus. Photo by K. S. Renzaglia.
  • Sphaerosporoceros adscendens. TEM showing immunocytochemical-labeling of RUBISCO in the pyrenoid. From Vaughn et al. (1990).



Updated May 17, 2004

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