If there's one thing you can count on, the more a plant is needed for a laboratory class, the less likely it will be available. Generally, the weedier a plant, the more you can count on it, so when you need some aerenchyma for a lab on cells and tissues, you grab some water lettuce (Pistia) and have at it. But the plantlets on duty today were all whimpy little things with almost no aerenchyma development at all. So you turn to the Cyperus (papyrus) and somebody needing to make a scroll had cut it all! Why this was as bad as discovering that the campus arborist had removed all the bayberry plantings without realizing that right there in exercise 11 it said to collect the waxy berries from the bushes on campus. What do they think the campus grounds are for if not to supply my classes with specimens? Fortunately the water hyacinth was marginally better, and while the petioles were rather elongated and narrow from too little sunlight, at least they have aerenchyma aplenty. Fortunately, the lesson on how to use a razor blade for cutting sections of plants without the letting of blood or the amputation of digits was highly successful. So you take the small victory.