Sense of Obligation Part 21

Lea was standing by the body when he came back, holding up the small power saw with a rotary blade. "Will this do?" he asked. "Runs off its own battery, almost fully charged, too."

"Perfect," she answered. "You're both going to have to help me." She switched into the Disan language. "Ulv, would you find some place where you can watch the street without being seen. Signal me when it is empty.

I'm afraid this saw is going to make a lot of noise."

Ulv nodded and went out into the bay, climbing a heap of empty crates so he could peer through the small windows set high in the wall. He looked carefully in both directions, then waved to her to go ahead.

"Stand to one side and hold the cadaver's chin, Brion," she said. "Hold it firmly so the head doesn't shake around when I cut. This is going to be a little gruesome. I'm sorry. But it'll be the fastest way to cut the bone." The saw bit into the skull.

Once Ulv waved them into silence, and shrank back himself into the shadows next to the window. They waited impatiently until he gave them a sign to continue again. Brion held steady while the saw cut a circle completely around the skull.

"Finished," Lea said and the saw dropped from her limp fingers to the floor. She ma.s.saged life back into her hands before she finished the job. Carefully and delicately she removed the cap of bone from the magter's head, exposing his brain to the shaft of light from the window.

"You were right all the time, Brion," she said. "There is your alien."

XVI

Ulv joined them as they looked down at the exposed brain of the magter.

The thing was so clearly evident that even Ulv noticed it.

"I have seen dead animals and my people dead with their heads open, but I have never seen anything like that before," he said.

"What is it?" Brion asked.

"The invader, the alien you were looking for," Lea told him.

The magter's brain was only two-thirds of its normal size. Instead of filling the skull completely, it shared the s.p.a.ce with a green, amorphous shape. This was ridged somewhat like a brain, but the green shape had still darker nodules and extensions. Lea took her scalpel and gently prodded the dark moist ma.s.s.

"It reminds me very much of something that I've seen before on Earth,"

she said. "The green-fly--_Drepanosiphum platanoides_--and an unusual organ it has, called the pseudova. Now that I have seen this growth in the magter's skull I can think of a positive parallel. The fly _Drepanosiphum_ also has a large green organ, only it fills half of the body cavity instead of the head. Its ident.i.ty puzzled biologists for years, and they had a number of complex theories to explain it away.

Finally someone managed to dissect and examine it. The pseudova turned out to be a living plant, a yeastlike growth that helps with the green-fly's digestion. It produces enzymes that enable the fly to digest the great amounts of sugar it gets from plant juice."

"That's not unusual," Brion said, puzzled. "Termites and human beings are a couple of other creatures whose digestion is helped by internal flora. What's the difference in the green-fly?"

"Reproduction, mainly. All the other gut-living plants have to enter the host and establish themselves as outsiders, permitted to remain as long as they are useful. The green-fly and its yeast plant have a permanent symbiotic relations.h.i.+p that is essential to the existence of both. The plant spores appear in many places throughout the fly's body--but they are _always_ in the germ cells. Every egg cell has some, and every egg that grows to maturity is infected with the plant spores. The continuation of the symbiosis is unbroken and guaranteed.

"Do you think those green spheres in the magter's blood cells could be the same kind of thing?" Brion asked.

"I'm sure of it," Lea said. "It must be the same process. There are probably green spheres throughout the magters' bodies, spores or offspring of those things in their brains. Enough will find their way to the germ cells to make sure that every young magter is infected at birth. While the child is growing--so is the symbiote. Probably a lot faster since it seems to be a simpler organism. I imagine it is well established in the brain pan within the first six months of the infant's life."

"But why?" Brion asked. "What does it do?"

"I'm only guessing now, but there is plenty of evidence that gives us an idea of its function. I'm willing to bet that the symbiote itself is not a simple organism, it's probably an amalgam of plant and animal like most of the other creatures on Dis. The thing is just too complex to have developed since mankind has been on this planet. The magter must have caught the symbiotic infection by eating some Disan animal. The symbiote lived and flourished in its new environment. Well protected by a bony skull in a long-lived host. In exchange for food, oxygen and comfort, the brain-symbiote must generate hormones and enzymes that enable the magter to survive. Some of these might aid digestion, enabling the magter to eat any plant or animal life they can lay their hands on. The symbiote might produce sugars, scavenge the blood of toxins--there are so many things it could do. Things it must have done, since the magter are obviously the dominant life form on this planet.

They paid a high price for their symbiote, but it didn't really matter to race-survival until now. Did you notice that the magter's brain is no smaller than normal?"

"It must be--or how else could that brain-symbiote fit in inside the skull with it?" Brion said.

"If the magter's total brain were smaller in volume than normal, it could fit into the remaining s.p.a.ce in the cranial hollow. But the brain is full-sized--it is just that part of it is missing, absorbed by the symbiote."

"The frontal lobes," Brion said with sudden realization. "This h.e.l.lish growth has performed a prefrontal lobotomy!"

"It's done even more than that," Lea said, separating the convolutions of the gray matter with her scalpel to uncover a green filament beneath.

"These tendrils penetrate farther back into the brain, but always remain in the cerebrum. The cerebellum appears to be untouched. Apparently just the higher functions of mankind have been interfered with, selectively.

Destruction of the frontal lobes made the magter creatures without emotions or ability for really abstract thought. Apparently they survived better without these. There must have been some horrible failures before the right balance was struck. The final product is a man-plant-animal symbiote that is admirably adapted for survival on this disaster world. No emotions to cause complications or desires that might interfere with pure survival. Complete ruthlessness--mankind has always been strong on this anyway, so it didn't take much of a push."

"The other Disans, like Ulv here, managed to survive without turning into such a creature. So why was it necessary for the magter to go so far?"

"Nothing is necessary in evolution, you know that," Lea said. "Many variations are possible and all the better ones continue. You might say that Ulv's people survive, but the magter survive better. If offworld contact hadn't been re-established, I imagine that the magter would slowly have become the dominant race. Only they won't have the chance now. It looks as though they have succeeded in destroying both races with their suicidal urge."

"That's the part that doesn't make sense," Brion said. "The magter have survived and climbed right to the top of the evolutionary heap here. Yet they are suicidal. How come they haven't been wiped out before this?"

"Individually they have been aggressive to the point of suicide. They will attack anything and everything with the same savage lack of emotion. Luckily there are no bigger animals on this planet. So where they have died as individuals, their utter ruthlessness has guaranteed their survival as a group. Now they are faced with a problem that is too big for their half-destroyed minds to handle. Their personal policy has become their planetary policy--and that's never a very smart thing. They are like men with knives who have killed all the men who were only armed with stones. Now they are facing men with guns and they are going to keep charging and fighting until they are all dead."

"It's a perfect case of the utter impartiality of the forces of evolution. Men infected by this Disan life form were the dominant creatures on this planet. The creature in the magters' brains was a true symbiote then, giving something and receiving something. Making a union of symbiotes where all were stronger together than any could be separately. Now this is changed. The magter brain cannot understand the concept of racial death, in a situation where it must understand to be able to survive. Therefore, the brain-creature is no longer a symbiote but a parasite."

"And as a parasite it must be destroyed!" Brion broke in. "We're not fighting shadows any more," he exulted. "We've found the enemy--and it's not the magter at all. Just a sort of glorified tapeworm that is too stupid to know when it is killing itself off. Does it have a brain--can it think?"

"I doubt it very much," Lea said. "A brain would be of absolutely no use to it. So even if it originally possessed reasoning powers they would be gone by now. Symbiotes or parasites that live internally like this always degenerate to an absolute minimum of functions...."

"Tell me about it? What is this thing?" Ulv broke in, producing the soft form of the brain-symbiote. He had heard all their excited talk but had not understood a word.

"Explain it to him, will you Lea, as best you can," Brion said, looking at her and realized how exhausted she was. "And sit down while you do it, you're long overdue for a rest. I'm going to try--" He broke off when he looked at his watch.

It was after four in the afternoon--less than eight hours to go. What was he to do? Enthusiasm faded as he realized that only half of the problem was solved. The bombs would drop on schedule unless the Nyjorders could understand the significance of this discovery. Even if they understood--would it make any difference to them? The threat of the hidden cobalt bombs would not be changed.

With this thought came the guilty realization that he had forgotten completely about Telt's death. Even before he contacted the Nyjord fleet he must tell Hys and his rebel army what had happened to Telt and his sandcar. Also about the radioactive traces. They couldn't be checked against the records now to see how important they might be, but Hys might make another raid on the strength of the suspicion. This call wouldn't take long, then he would be free to tackle Professor-Commander Krafft.

Carefully setting the transmitter on the frequency of the rebel army, he sent out a call to Hys. There was no answer.

There was always a chance the set was broken. He quickly twisted the transmitter to the frequency of his personal radio, then whistled in the microphone. The received signal was so loud that it hurt his ears. He tried to call Hys again, and was relieved to get a response this time.

"Brion Brandd here, can you read me? I want to talk to Hys at once."

Shockingly, it was Professor-Commander Krafft who answered.

"I'm sorry Brion, but it's impossible to talk to Hys. We are monitoring his frequency and your call was relayed to me. Hys and his rebels lifted s.h.i.+p about a half an hour ago, and are already on the way back to Nyjord. Are you ready to leave now? It will soon become dangerous to make any landings. Even now I will have to ask for volunteers to get you out of there."

Hys and the rebel army gone. Brion a.s.similated the thought at the same moment he realized he was talking to Krafft. He was thrown off balance, not prepared for the encounter.

"If they're gone--well, then there's nothing I can do about it," Brion said. "I was going to call you, so I can talk to you now. Listen and try to understand. You must cancel the bombing. I've found out about the magter, found what causes their mental aberration. If we can correct that, we can stop them from attacking Nyjord--"