1. Sagittaria - Alismataceae -Alismatales:

Species of this genus are usually monoecious. EXAMINE both staminate and pistillate flowers and CONSTRUCT a floral formula for each. Please work in pairs or observe demo material.
 
FLORAL FORMULA (staminate): ________________
FLORAL FORMULA (pistillate): ________________
KEY to family. Which floral characteristic allows you to determine the proper class?___________________________________
COUPLET SEQUENCE: __________________________________________
SKETCH your male and female flowers:

In your opinion, with what dicot family would the Alismataceae be most easily confused? _________________________
The Alismatidae represent a fundamental, relatively unspecialized group of monocots, analogous to the Magnoliidae of the Magnoliopsida. What is "primitive" about the floral structure of Sagittaria? ___________________________

These spiderwort flowers are best observed in water (use a small dish). This flower shows advanced characteristics in comparison to the apocarpous Sagittaria, but is primitive when compared to elements of this subclass that have adapted to anemophily (e.g., the Cyperales).
NOTE the basic "monocot" floral plan, i.e., 3 sepals, 3 petals, 3 connate carpels and 6 stamens. The pubescent filaments and bow-tie shape anthers are characteristic of Tradescantia. SKETCH your flower and its featurs:

NOTE that the other important genus in the family, Commelina, has zygomorphic flowers with two large petals and the third much smaller.

Flowers of this order are highly reduced in comparison to those of the entomophilous Commelinales (see W&K p. 447 and wall chart.) In this family, the perianth has been reduced to lodicules; the flower is simply 3 stamens and a compound pistil.

Each flower is enclosed by two bracts: the larger bract (LEMMA) usually encloses the smaller bract (PALEA) and the flower. This unit - two fertile bracts and the flower - is known as the FLORET. The floret is NOT the basic unit of a grass inflorescence. The basic unit is the SPIKELET, a group of florets (sometimes just one) subtended by two STERILE BRACTS (bracts not in direct association with a flower) known as GLUMES (see fig. 20-7, 20-8 in W&K, p. 447, 449 and the wall chart). Identification of grass species requires an ability to recognize this basic unit, the spikelet.

EXAMINE an oat spikelet. NOTE the two basal glumes which completely enclose the florets. There should be three florets above the glumes, with the terminal one not completely developed. SEPARATE a palea from the larger lemma that encloses it. Note the flower. Is there any structural difference between the palea and lemma? ______ Look at the margins.
DIAGRAM this Avena spikelet, pointing out glumes, florets, and palea and lemma of one floret.

NOW OBTAIN a Bromus spikelet and DIAGRAM its basic structure i.e., glumes and paleas and lemmas of each floret.

EXAMINE specimens of other grass genera on display, especially such economically important plants as Triticum (wheat), Zea mays (corn), and Oryza sativa (rice). Remember that lawns and ornamental grasses are important as well. Be sure that you can identify the basic unit of the inflorescence of each -- the spikelet. 

4. Carex - Cyperaceae - Cyperales:

NOTE the vegetative differences between Cyperaceae (sedges) and Poaceae (grasses). Sedges tend to have angled stems.
LIST two other vegetative differences: _________________________ and ___________________-
EXAMINE a Carex floret. NOTE the sack-like PERIGYNIUM surrounding the ovary--this is a feature only of Carex.
EXAMINE the Carex inflorescence. It is made of "spikelet-like" units, but the similarity between Cyperaceae "spikelets" and Poaceae spikelets is superficial. LIST two differences for grass and sedge inflorescences.
1._______________________________________________________________
2._______________________________________________________________
SKETCH inflorescence, flower, perigynium, and ovary of Carex: 

5. Juncus (Rush) - Juncaceae - Juncales:

Members of the Juncaceae are also likely to be mistaken for Grasses (Poaceae). Carefully EXAMINE your Juncus specimen and construct a floral formula.
FLORAL FORMULA: ___________________________________________

NOTE presence of a PERIANTH in this family. Also, what is the fruit type?
LIST two vegetative characters that could be useful in distinguishing Juncus from a grass or sedge:
1._______________________________
2._________________________________
SKETCH a Juncus flower: