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Flashcards in Development of classification Deck (47):

Historia Planatarum

Theophrastus, Forms systems


Theophrastus classified all plants on the basis of the following characters:

• trees, shrubs, subshrubs, herbs
• annuals, biennials, perennials
• flowering versus nonflowering
• superior ovary versus inferior ovaries.
• free petals (polypetaly) versus fused petals (gamopetaly).


Historia Naturalis

Caius Plinius Secundus, “Pliny the Elder”
37-volume work


De Materia Medica

Pedanios Dioscorides
Roman military surgeon
For 1500 years this was universally considered the major work on plants.


De Vegetabilis

Albertus Magnus
-first to recognize, on the basis of stem structure, the differences between monocots and dicots


Herbarium Vivae Eicones

Otto Brunfels
-His work became known as an herbal.
-took most of its information from the writings of Theophrastus, Dioscorides, and Pliny


De Historia Stirpium

Leonhart Fuchs
-illustrated by woodcuts


his Herbal, the first botanical work in English

William Turner
“Father of English Botany.”


Rariorum Plantarum Historia

Charles Clusius


Badianus Manuscript

Aztec herbal


best known for “inventing” or at least making popular the use of the herbarium

Luca Ghini


De Plantis Libri

Andrea Caesalpino
-First Plant Taxonomist


Caesalpino classified plants based on:

habit (trees, shrubs, herbs)
• fruit type
• ovary (superior versus inferior)
• root system (tap versus fibrous)
• presence or absence of latex
• number of locules in an ovary


Pinax Theatri Botanica

Gaspard Bauhin


first botanist to distinguish between genus and species

Gaspard Bauhin


Historia Plantarum Universalis

Jean Bauhin
-excellent diagnosis


Methodus Plantarum Nova

John Ray


John Ray Classification system based on:

habit (woody versus herbaceous)
• dicots versus monocots
• fruit types
• leaf types
• flower features



Pierre Magnol
-He was the first to use families in the sense that they are used today


Institutiones Rei Herbariae

Joseph Pitton de Tournefort
-Father of the Genus Concept.”


Tournefort classified flowers based on:

petals versus no petals (apetalous)
• petals (free versus united)
• corolla shape (regular versus irregular)


Species Plantarum

Carl Linnaeus
-“Father of Taxonomy.”
-Systema Naturae (1735), Genera Plantarum (1737), and Hortus Cliffortianus (1738).
-Linnaeus assisted Johannes F. Gronovius (1686-1762) in describing the plants collected by John Clayton (1686-1773) in Virginia in Flora Virginica (1739, 1743).
-Peter Kalm


Species Plantarum's greatest significance lies in the consistent use of the binomial system of nomenclature, that is, a single generic name along with a single specific epithet

Linnaeus arranged this book according to the sexual system outlined in Systema Naturae. He divided the plants into 24 classes based largely on the number, union and length of stamens.
The classes were divided into orders based on the number of styles in each flower. Although some related genera were associated in this “Sexual System,” it was still an artificial classification.



The development of a classification system reflecting natural relationships became a major focus of botanical activity. In its original context, the natural system was designed to reflect God's plan of creation and not one of lineages.


Michel Adanson

arranged plants into groups similar to our orders and families
-Familles des Plantes


empirical approach

Adanson emphasized that many characters should be used in a classification scheme, and that equal weight should be placed on each unless detailed studies showed that some were more important taxonomically. This is called the empirical approach


De Jussieu family

Antoine, Bernard, Joseph, Antoine-Laurent (major step towards natural plant families)


Antoine-Laurent divided plants into three major groups

Acotyledones (cryptogams and a few misplaced monocots)
• Monocotyledones (monocots)
• Dicotyledones (dicots and gymnosperms).


De Candolle family

Augustin Pyramus De Candolle, Alphonse
-They divided plants into two major groups:
• Cellulares (nonvascular)
• Vasculares (vascular)
-began dicots with Ranunculaceae


George Bentham and Joseph Dalton Hooker

Genera Plantarum
-The dicots were divided into three groups:
• Polypetalae (free petals)
• Gamopetalae (fused petals)
• Monochlamydeae (apetalous)
-species concepts were based on the idea that species are fixed entities, unchanged through time and placed on the earth by the Creator.
British herbaria, such as Kew and the British Museum, are still arranged according to the Bentham and Hooker system
(pre darwin)



Darwin's Origin of Species (1859) did much to alter the basic concepts used in determining relationships. Attempts to follow his principles resulted in systems that arranged natural groups in a phylogenetic (evolutionary) sequence progressing from the simplest (most primitive) to the more complex (most advanced).


August Wilhelm Eichler system

based his system on morphological information
-For example, his system divided the non-seed plants into the:
• Thallophyta (liverworts)
• Bryophyta (mosses)
• Pteridophyta (ferns and allies)


System still used in most non-British herbaria.

Adolph Engler (1844-1930) and Karl Prantl (1849- 1893), and is referred to as the Englerian School.


Englerian School

-now considered incorrect (equated “simple” with “primitive)
Monocots preceded the dicots in this system, and dicots were divided into the:
• Archichlamydeae (free petals or no petals) • Metachlamydeae (fused petals)

-Engler considered plants with simple, unisexual flowers to be primitive. The first group of dicots were the Amentiferae (wind- pollinated, catkin-bearing plants and their relatives). Modern families with these traits are Betulaceae, Fagaceae, and Juglandaceae.


Charles Bessey

Outlines of Plant Phylaflowering plants began with the Magnoliaceae- Ranunculaceae complex.
-This complex was comprised of primarily insect-pollinated plants. This group gave rise to the other dicots and to the monocots. He considered the wind pollinated Amentiferous families to be secondarily reduced.


Bessey's system

Bessey’s system, which was really a modified Bentham and Hooker classification, was based on a set of dicta or concepts of primitive features found in ancient plants versus the advanced characters of more recently evolved plants.



woody preceded herbs, vines, and climbers
• perennials preceded biennials and annuals
• vascular bundles in a ring (dicots) preceded vascular bundles scattered (monocots)
• alternate leaves preceded opposite or whorled leaves
• simple leaves preceded compound leaves
• bisexual flowers preceded unisexual flowers
-many-parted flowers preceded few-parted flowers
• actinomorphic (regular) flowers preceded zygomorphic (irregular) flowers
• separate perianth parts preceded fused perianth parts
• flowers with petals usually preceded apetalous ones
• many separate stamens preceded few or united stamens
-hypogyny (superior ovary) preceded epigyny (inferior ovary)
• generally, numerous separate carpels preceded fewer, fused carpels
• pollen grains with one pore preceded those with three pores
• axile placentation preceded free central placentation
• simple fruits preceded aggregate fruits


Bessey’s Cactus

attempted to show the interrationships among the various orders he recognized.


John Hutchinson

The Families of Flowering Plants provided ready keys and descriptions to the families.


Hutchinson divided the angiosperms into

Monocotyledones (monocots)
• Herbaceae Dicotyledones (herbaceous dicots)
• Lignosae Dicotyledones (woody dicots)
-He suggested that monocots were derived from certain primitive herbaceous dicots (Ranales), and all other herbaceous dicots were also derived from the Ranales
-The woody dicots were said to be derived from the Magnoliales
-major flaw was this division of the dicots into a woody versus herbaceous lines
-but excellent family descriptions



Takhtajan, cronquist, Thorne, and dalgren


Armen Takhtajan

Takhtajan described the earliest angiosperms as follows:
• small woody plants
• leaves simple, entire, and pinnately veined
• flowers solitary, of moderate size, arrangement terminal and axillary
-flowers actinomorphic, bisexual
• numerous sepals, petals, stamens, and carpels
• stamens leaflike, pollen monosulcate
• carpels unsealed, conduplicate with the stigmatic surface along the margin

These would have been similar to members of the present-day Magnoliaceae.

Magnoliales was the most primitive group of flowering plants, and all others evolved from it. He believed that the monocots evolved from a precursor of the order Nymphaeales

recognized the classes Magnoliopsida and Liliopsida in the Phylum Magnoliophyta


Arthur Cronquist

agreed with Takhtajan but Cronquist recognized 11 subclasses (instead of 10)
-Cronquist included Takhtajan's Ranunculidae in his own Magnoliidae. In addition, he divided Takhtajan's Liliidae into his Liliidae, Commelinidae, and Zingiberidae.


Robert Thorne

57 orders and 395 families in the two subclasses Dicotyledoneae and Monocotyledoneae
- 'phylogenetic shrub'


Rolf Dalgren’s

placed all of the angiosperms in Class Magnoliopsida
-He did not recognize subclasses in the same sense that Cronquist and Takhtajan did, although he did distinguish between the dicots (subclass Magnoliidae) and monocots (subclass Liliidae) as distinct groups


According to the englerian school dicotyledons began with:



According to the Besseyan school dicotyledons began with: