PLS 831

   Taxonomy of Ornamental Plants

    Spring 1999

             Test 1

                                    Name ________________________________________

Part I.  Short Answer.  Answer each of the following question, in the space provided, with concise answers.

1.   Please indicate (by circling) which character in each pair represents the most derived state.  (10 points)

perianth -             absent            present

            imbricate            valvate or convolute

            differentiated            undifferentiated

stamens -             laminar            differentiated into anther & filament

            dehiscent by pores            dehiscent by slits

            staminods absent            staminods present

pistils -            compound            simple

            inferior            superior

            spiral            whorled         

ovules -            placentation axile            placentation free-central

2.   Order 3 subclasses of the Liliopsida from the most ancestral to the most derived.  (5 points)

3.   What are the names of three groups of non-vascular plants?  (5 points)

4.      What is the difference between the Gymnospermae and the Pinophyta?  What taxonomic rank is each?  What is the derivation of the term Pinophyta? (10 points)

5.      We considered the phylogentic trees of the dicotyledon families as proposed by Goldberg and by Cronquist.  Which is more correct?  (10 points)

6.      Draw (diagram or define) the following leaf, flower and fruit: Leaves alternate, simple, very short petiolate, petioles, pubescent proximally; blades leathery, pinnately veined, mostly long-elliptical, 8-16 cm long and 3-5 cm wide, cuneate basally, apices obtuse to acute, sometimes notched, margins very shallowly appressed crenate-serrate, upper surfaces glabrous, dark green, the lower more or less olive-green, sparsely pubescent with hairs as on the twigs, the hairs sometimes sloughed as the leaves age.

      Flowers solitary, axillary to close-set leaves on twigs of the season, their stiff stalks 5-8 cm long, usually on a given twig but blooming one at a time, usually a few at one time on the tree as a whole, the flower period extending over a a number of weeks in the summer.  Flowers 8 cm across; sepals 5, short clawed at the base, their blades sub-orbicular, silky pubescent exteriorly, deciduous; petals 5, white, united at the base, margins crinkly fringed, their broadly rounded tips turne up, silky pubescent exteriorly; stamens numerous, yellow, the filaments united basally into a 5-lobed cup, each lobe flush against the base of the petal; pistil one, superior, ovoid, 5 locular.  Fruit a hard, woody capsule, ovate-oblong capsule about 1.5 cm long, its surface appressed silky-pubescent, dehiscing loculicidally, each locule with 4-8 flat, winged seeds about 1 cm long. (10 points)

Part II.  Essay. 50 points.  Please answer the following questions with complete, clearly written statements.  Do not exceed the space provided for each question (front and back of this page).

1.      Write a key, based on floral characteristics, to separate the following ten families (20 points):

Aceraceae

Berberidaceae

Betulaceae

Illiciaceae

Lauraceae

Oleaceae

Ranunculaceae

Theaceae

Thymelaeaceae

Ulmaceae

Diagram Cronquist's organization of the Magnoliopsida subclasses and indicate to which each of the above families belong (10 points).  Justify the organization of the subclasses (from ancestral to derived) based on floral morphology using the above families as examples (20 points).