More recondite for Mr. Belloc is the work of Hilgendorf upon _Planorbis_, because it is in German; but the drift of it is visible in the Palæontology wing of the London Natural History Museum, Room VIII. A species of these gasteropods was, during the slow processes of secular change, caught in a big lake, fed by hot springs. It underwent progressive modification into a series of successive new species as conditions changed through the ages. Dr. Klähms’ specimens show this beautifully. Rowe’s account of the evolutionary series in the genus _Micraster_ (_Q.J.M.S._, 1899) is also accessible to Mr. Belloc, and he will find other matter to ponder in Goodrich’s _Living Organisms_, 1924. The finest series of all, longer in range and completer in its links, is that of the Horse. There is an excellent little pamphlet by Matthew and Chubb, well illustrated, _The Evolution of the Horse_, published by the American Museum of Natural History, New York, so plain, so simple, so entirely and humiliatingly destructive of Mr. Belloc’s nonsensical assertions, that I pray him to get it and read it for the good of his really very unkempt and neglected soul. Thus we observe that Mr. Belloc does not know the facts in this case of Natural Selection, and that he argues very badly from such facts as he misconceives. It is for the reader to decide which at the end is more suitable as a laughing-stock--the Theory of Natural Selection or Mr. Belloc. And having thus studied this great Catholic apologist as an amateur biologist and arrived at the result, we will next go on to consider what he has to say about the origins of mankind--and Original Sin. IV MR. BELLOC’S ADVENTURES AMONG THE SUB-MEN: MANIFEST TERROR OF THE NEANDERTHALER