If you’re looking for the typical Blish SF novel….keep going. This is more of an African adventure in the Belgian Congo that takes place in 1906. It reads like a 1930’s jungle movie with dinosaurs.
Kit Kennedy has lived in the Congo for twelve years. He used to be a teacher in Kansas but got a fifteen year old girl pregnant and was run out of town. The Belgian authories let him stay and he has friendly relations with the natives including a local king Tombu.
The Resident Magistrate tells Kit to lead a safari. The group consists of Paula Lee and her doctor husband. They rarely speak to each other. She works for the British government. Another member is Stahl who is accompanied by a group of Belgian marines. Their leader is Captain van Bleyswijck.
There are rumors of night shapes, or demons, strange looking and dangeous animals. Native drums warn them not to proceed. Stahl insist they move on. Their destination is a pitchblende mine worked by slave labor. Due to the radium content the slaves look like leprosy victims. Before they get to the mine the safari is attacked by hostile natives. Kit is up a tree and is caught by a python.
When he gets back down Tombu tells him the safari has been taken prisoner. When they get to the village Kit finds out that they’re cannibals. He sneaks into a tent where Stahl and Paula are being held. Her husband has been killed.
On the way to the village Kit is accompanied by the python who has some kind of attachment to him. That gives pause to the superstitious natives. Kit challenges the chief to a battle on top of a huge drum.
Later on there’s another battle. This time between the python and the legendary beast. It’s a dinosaur.
Now it’s a year later and Kit is still accompanied by the python. Word comes that another safari is on its way. This one wants to go the valley where the dinosaurs live. Kit doesn’t want to take them there. He calls on a witch doctor for help.
If Blish or anyone else had written this in the 30’s it would have been filmed. This fits right in with all the jungle pictures and serials of the era. It’s old fashioned jungle fun.
Triceratops-One of the night beasts
Vintage45's Blog 
Yikes, “this is more of an African adventure in the Belgian Congo that takes place in 1906. It reads like a 1930′s jungle movie with dinosaurs” — sounds downright awful. I do love a few of Blish’s works….
This is okay if you like cheez and some of those awful movies like “White Pongo” and other apefests. This doesn’t have apes but just about everything else.