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Eastern Illinois University

Velamen

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Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara S. Carlsward, William Louis Stern Jan 2009

Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara S. Carlsward, William Louis Stern

Barbara S. Carlsward

Triphorinae represents a group of three anatomically simple genera, the structural features of which are unspecialized. The anomocytic stomatal pattern occurs in all genera; it predominates in Triphora . A foliar hypodermis, sclerenchyma, fibre bundles and stegmata are absent. The mesophyll is homogeneous. The exodermal and endodermal cells in the roots are entirely thin-walled and tilosomes are absent. However, there are anatomical modifications that appear to be unique: root hairs in Monophyllorchis are borne on velamenal buttresses and, in Psilochilus , they arise endogenously. In the root vascular system of Psilochilus , the metaxylem occurs as a circumferential band. The …


Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara S. Carlsward, William Louis Stern Jan 2009

Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara S. Carlsward, William Louis Stern

Faculty Research & Creative Activity

Triphorinae represents a group of three anatomically simple genera, the structural features of which are unspecialized. The anomocytic stomatal pattern occurs in all genera; it predominates in Triphora . A foliar hypodermis, sclerenchyma, fibre bundles and stegmata are absent. The mesophyll is homogeneous. The exodermal and endodermal cells in the roots are entirely thin-walled and tilosomes are absent. However, there are anatomical modifications that appear to be unique: root hairs in Monophyllorchis are borne on velamenal buttresses and, in Psilochilus , they arise endogenously. In the root vascular system of Psilochilus , the metaxylem occurs as a circumferential band. The …


Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara Carlsward, William Stern Jan 2009

Vegetative Anatomy And Systematics Of Triphorinae (Orchidaceae), Barbara Carlsward, William Stern

Faculty Research & Creative Activity

Triphorinae represents a group of three anatomically simple genera, the structural features of which are unspecialized. The anomocytic stomatal pattern occurs in all genera; it predominates in Triphora . A foliar hypodermis, sclerenchyma, fibre bundles and stegmata are absent. The mesophyll is homogeneous. The exodermal and endodermal cells in the roots are entirely thin-walled and tilosomes are absent. However, there are anatomical modifications that appear to be unique: root hairs in Monophyllorchis are borne on velamenal buttresses and, in Psilochilus , they arise endogenously. In the root vascular system of Psilochilus , the metaxylem occurs as a circumferential band. The …


Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Louis Stern, Barbara S. Carlsward Jan 2008

Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Louis Stern, Barbara S. Carlsward

Barbara S. Carlsward

Calypsoeae represent a small tribe of anatomically little-known orchids with a wide distribution in the Western Hemisphere. Leaves are present in all genera, except Corallorhiza and Wullschlaegelia both of which are subterranean taxa. Stomata are abaxial (ad- and abaxial in Aplectrum) and tetracytic (anomocytic in Calypso). Fiber bundles are absent in leaves of all taxa examined except Govenia tingens. Stegmata are present in leaves of only Cremastra and Govenia. Roots are velamentous, except in filiform roots of Wullschlaegelia. Vegetative anatomy supports a relationship between Wullschlaegelia and Corallorhiza but does not support the grouping of winter-leaved Aplectrum and Tipularia nor proposed …


Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Louis Stern, Barbara S. Carlsward Jan 2008

Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Louis Stern, Barbara S. Carlsward

Faculty Research & Creative Activity

Calypsoeae represent a small tribe of anatomically little-known orchids with a wide distribution in the Western Hemisphere. Leaves are present in all genera, except Corallorhiza and Wullschlaegelia both of which are subterranean taxa. Stomata are abaxial (ad- and abaxial in Aplectrum) and tetracytic (anomocytic in Calypso). Fiber bundles are absent in leaves of all taxa examined except Govenia tingens. Stegmata are present in leaves of only Cremastra and Govenia. Roots are velamentous, except in filiform roots of Wullschlaegelia. Vegetative anatomy supports a relationship between Wullschlaegelia and Corallorhiza but does not support the grouping of winter-leaved Aplectrum and Tipularia nor proposed …


Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Stern, Barbara Carlsward Jan 2008

Vegetative Anatomy Of Calypsoeae (Orchidaceae), William Stern, Barbara Carlsward

Faculty Research & Creative Activity

Calypsoeae represent a small tribe of anatomically little-known orchids with a wide distribution in the Western Hemisphere. Leaves are present in all genera, except Corallorhiza and Wullschlaegelia both of which are subterranean taxa. Stomata are abaxial (ad- and abaxial in Aplectrum) and tetracytic (anomocytic in Calypso). Fiber bundles are absent in leaves of all taxa examined except Govenia tingens. Stegmata are present in leaves of only Cremastra and Govenia. Roots are velamentous, except in filiform roots of Wullschlaegelia. Vegetative anatomy supports a relationship between Wullschlaegelia and Corallorhiza but does not support the grouping of winter-leaved Aplectrum and Tipularia nor proposed …


Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward Jan 2004

Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward

Barbara S. Carlsward

On the basis of floral and vegetative morphology, 63 tropical American genera have been recognized within Maxillarieae. We were able to examine anatomical material of all subtribes, excluding Oncidiinae. Stegmata with conical silica bodies occur in leaves and stems of all subtribes excluding Ornithocephalinae, and pericyclic stegmata found in roots are characteristic of Lycastinae. Lycastinae and Maxillariinae are characterized by foliar glands, foliar fibre bundles and tilosomes. Endodermal cells are U-thickened in most Zygopetalinae; O-thickened in most Lycastinae, Ornithocephalinae and Telipogoninae; variously thickened in Maxillariinae; and thin-walled in Cryptarrhena lunata. Water-storage cells varied from thin-walled to variously banded throughout Maxillarieae. …


Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward Jan 2004

Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Louis Stern, Walter S. Judd, Barbara S. Carlsward

Faculty Research & Creative Activity

On the basis of floral and vegetative morphology, 63 tropical American genera have been recognized within Maxillarieae. We were able to examine anatomical material of all subtribes, excluding Oncidiinae. Stegmata with conical silica bodies occur in leaves and stems of all subtribes excluding Ornithocephalinae, and pericyclic stegmata found in roots are characteristic of Lycastinae. Lycastinae and Maxillariinae are characterized by foliar glands, foliar fibre bundles and tilosomes. Endodermal cells are U-thickened in most Zygopetalinae; O-thickened in most Lycastinae, Ornithocephalinae and Telipogoninae; variously thickened in Maxillariinae; and thin-walled in Cryptarrhena lunata. Water-storage cells varied from thin-walled to variously banded throughout Maxillarieae. …


Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Stern, Walter Judd, Barbara Carlsward Jan 2004

Systematic And Comparative Anatomy Of Maxillarieae (Orchidaceae), Sans Oncidiinae, William Stern, Walter Judd, Barbara Carlsward

Faculty Research & Creative Activity

On the basis of floral and vegetative morphology, 63 tropical American genera have been recognized within Maxillarieae. We were able to examine anatomical material of all subtribes, excluding Oncidiinae. Stegmata with conical silica bodies occur in leaves and stems of all subtribes excluding Ornithocephalinae, and pericyclic stegmata found in roots are characteristic of Lycastinae. Lycastinae and Maxillariinae are characterized by foliar glands, foliar fibre bundles and tilosomes. Endodermal cells are U-thickened in most Zygopetalinae; O-thickened in most Lycastinae, Ornithocephalinae and Telipogoninae; variously thickened in Maxillariinae; and thin-walled in Cryptarrhena lunata. Water-storage cells varied from thin-walled to variously banded throughout Maxillarieae. …