Chapter the Third

An Interruption

"But didn't he also make a series of comparisons between the growing plant and animal tissues?" Makyatta asked, not yet sensing the direction Mendel wanted to take.
"Yes, yes," said Mendel somewhat sharply, "he has indeed compared the growth of plant parenchyma to the growth of the animal notochord, but I think he is wrong to interpret cartilage as a matrix from which and in which cells are formed."
"Why is that?"
"Because ..." he stumbled for an idea, "it does not seem reasonable to suppose, as Schwann says, that cells first send out their nucleus into the 'cytoblastema' where they make a wall that expands, filling with fluid. I have read this work, and it does not fit with newer work on the production and division of cells." "But ..." Makyatta tried to interrupt, but failed.
"Also," Mendel overroad him, "Schwann has had these 'theories of cells' before, and his 'crystallization peculiar to organic substances' concept of cell growth is particularly embarrassing."

"I do not agree," Makyatta said, trying not to contradict Mendel in front of his class, but simply to keep him honest and back up his arguments with proper reasoning. "I remember that Felix Dujardin has used the term 'sarcode' to refer to this glutinous substance."
"And you think this is the same as Schwann's 'cytoblastema'?"
"I don't know, but what term would you use?"
Mendel thought for a moment. "I like the term - 'protoplasm' ", he said after a moment, then went on to explain why. "J.E. Purkinje introduced the term in 1840, but I don't remember anyone using it until Hugo von Mohl re-introduced it in 1846. All studies since then have shown that both plant and animal cells share this 'small naked piece of protoplasm with the nucleus within it', but that plants also are surrounded by a hard cell wall."

"However," Mendel went on, "my friend Carl Nageli prefers the term 'schleimschicht'," glad to get onto the topic of Nageli's work.
"But it was Hugo von Mohl who has made it clear that all plant cells have walls, is it not?" Makyatta asked.
"At least in lower plants," Mendel qualified, "but it is true that his work and that of Max Schultze, are slowly convincing most people that protoplasm is the common substance of all cells, although some older botanists and anatomists still hold to the view that cells are simple vesicles. But, the work of Nageli ..."

Once again he was doomed. "Please, sir," came a soft, tiny voice from the doorway. Mendel jumped slightly, he couldn't see the door from where he was standing. "Yes boy," he said, seeing that the voice came from a small messenger standing on one leg, "what do you want?"
"If it please you sir, Doktor Auspitz sends his respects and could you please come to his office as soon as is convenient?"
Mendel wrinkled his brow, such a request was not unusual but to receive a personal summons in the middle of a class period was most irregular. Despite the careful and polite phrasing it was obvious that the Headmaster wished to see him right away.
"Thank you, boy. Please inform Dr Auspitz that I will come presently." By which Mendel meant that he would come at once.
"Yes sir, thank you sir," exclaimed the boy at the door, and he vanished.

Turning to his old schoolteacher, Mendel said in puzzled tones, "The Headmaster wishes to see me. I wonder if you would be good enough to excuse me for a moment? Boys, take out your books."
A silent groan ran around the room. "Open them to the chapter on plant form and function. Read from the beginning of the chapter to the section on the relationship of leaf size to plant growth. When I return I will examine you on how well you have understood the concept of surface area." The silent groan became louder, but Mendel had already turned back to Makyatta.
"Perhaps you could ...?"
"Of course, I would be delighted to stay with your boys," Makyatta nodded, reading Mendel's thoughts. There was absolutely no doubt in either teacher's mind that their classroom of boys would remain dutifully engaged in study while both of them were absent, but ...