Think of what follows as a serious comic strip. It's the record of my having seen several Colpoda excyst. I've added colors to make the parts of the images easier to recognize. The white background is factual bright-field, and the cyst wall is close to the color I actually saw. In fact, as you probably know already, the organisms and the inside of their cyst were various shades of transparent. I've given one of the encysted critters a vacuole it did not develop until the second or third panel, the better for you to know which one is the main or title "character."
 

Only one day after I made an infusion from old, sun-baked cattle manure, I noticed that Colpoda had appeared and were an average of 40 microns in length. When the infusion was about 48 hours old, Colpoda were still the only protists active; some were 60 microns long (yesterday's critters now well fed?) but most were the smaller size. I noticed some round objects, 40 microns in diameter, apparently organic with a thick outer membrane or wall and indeterminate contents. Then I saw one that was different: there was a moving triangle attached to it, there were whirls in the water and bacteria outside of it, and some things inside it were tumbling and rotating not quite fast enough to be a blur. I began to pay close attention.

This incident, from the first cartoon panel to the last, took about two hours. The biggest, strongest young Colpoda never got out of the resting cyst. The process and its results raise some questions.

Since I came upon the cyst with one Colpoda outside already, I don't know if any had emerged earlier. According to Gravé, Colpoda resting cysts usually contain one individual, but his micrographs are of Colpoda aspera, whereas the critters I saw look most like the Jahns' drawing of Colpoda cucullus in How to Know the Protozoa; the organisms I watched excyst are pretty surely some Colpoda species. In the same infusion, later, I found (on five slides) twenty-five more cysts with multiple occupants, and no cysts with just one. So I'd say it's normal for this species of Colpoda to multiply after encysting.

For four reasons—the sturdiness of the outer cyst covering, the lack of external cilia on the cyst, the difficulty experienced by the young in getting out, and the range-dried state of the infusion material—I'm sure the cysts I saw were resting cysts, not reproductive ones. (Gravé says that Colpoda form cysts to reproduce: one organism encysts, division takes place, and four or sometimes eight new individuals emerge; but they emerge from a ciliated reproductive cyst simultaneously with the cyst's breaking apart into four or eight pieces.)

Okay. But what about the last two critters in the cyst I watched? If the main character had eaten its cyst-mate, I would have noticed a food vacuole and its contents. But what I saw was that there were two Colpoda in the cyst and then there was one; the simplest explanation is that, moving about, the larger organism (and probably the others, earlier) battered the smaller one until it decompressed— until its outer membrane weakened, and burst, and let its cytoplasm escape into the medium inside the cyst. Since the left-over pieces of the earlier-emerging Colpoda had apparently dissolved, the even littler pieces of the fifth Colpoda should have dissolved, too. By the end, there was nothing in the cyst but the fourth, large Colpoda. 

Now, here is where the main character becomes a hero, much more than the Hemingway character that my title alludes to.* Altruism. It's a word that occurs in glossaries of biological terms. In this case, as in most cases of biological altruism, the self-sacrifice isn't intentional or conscious; it just happens, and if it works when it happens, we call it an instance of natural selection. Looking at those little Colpoda squeezing through the exit, I wondered how they did it. The hole may have gotten larger with use, but none of the emergent organisms simply swam out; they went in the exit, they came partly out of the exit on its other side, they came virtually all the way out of the exit, and then they swam away when their attachment broke. 

Question:  what did they have that the last Colpoda didn't —besides the luck and/or biological inclination to get into the exit hole sooner?  Answer:  bodies inside the cyst to push against while they were squeezing through. As more of the Colpoda emerged, one body, growing bigger by the minute, remained.  It did its job.