When Huxley was appointed Professor of Natural History at the Royal School of Mines in 1854, he did not look forward to the role of paleontologist. He had been far less interested in fossils than were Charles Darwin and Richard Owen. But his primary interest began to shift from the study of marine invertebrates to that of living and fossilized vertebrates; and his involvement in paleontology and geology is to be seen in the papers he wrote popularizing those scientific disciplines and in his being a member and president of the Geological Society. From November 1858 to September 1875, with the Reverend Charles Gordon and others, he investigated the Elgin sandstones in pursuit of dinosaurian and other fossil remains. The investigation of matters such as fossilized footprints and jaws resulted in letterse.g., December 8, 1858 (in which he offers his kingdom for a tooth) and in a dozen papers, such as "On the Stagonolepis Robertsoni (Agassiz) of the Elgin Sandstones" (1859) and "On a New Specimen of Telerpeton Elginense" (1867)November 22, 1866, Huxley much coveting the Telerpeton reptile for Jermyn Street. He continued commenting on the Elgin finds for two decadesGeological Society (1887).
A creature on whom he reflected throughout his life was Labyrinthodont, as in his November 27, 1865 letter to Lyell and his article on amphibia for the Encyclopedia Britannica.
Shortly after his return to England, Huxley assailed Professor Owen for making a mistake about the existence of certain fossil reptilesto W. Macleay, November 9, 1851. A serendipitous benefit of the trips he would take for a naturalists' survey or fisheries commission during the 1850s was to explore for fossil reptiles and other creatures, and to set up communication with others who would exhume and send him speciments. At the end of the decade, he wrote to Charles Lyell supporting the opinion he sharedwith Lyell, on the persistence of animal types, for example the crocodileJune 25, 1859.
In the 1859 On The Theory of the Vertebrate Skull, Huxley drew anatomical connections between reptiles and birds. But nothing existed then as a likely reptilian ancestor for brids. The 1858 unearthing of the crocodile-sized Stagonolepis and the "whale reptile" Cetiosaurus, which Huxley looked upon as a "Frankensteinosaurus," dug up in 1868, were far too large, in Huxley's view "the largest animal that ever walked upon the earth." He caught relative grandeur in a doodle:
But better news, a better gospel, was to be investigatedCompsognathus, no larger than a chicken, a feasible "missing link" connecting birds to dinosaurs. In 1863, Huxley concluded a response to a letter from Charles Kingsley requesting an article on prayers, that he was busy doing an article on reptilesOctober 4, 1860. He soon turned his attention to the evolution of birds from reptilesJanuary 21, 1869 (to Haeckel).
In Palæontology and the Doctrine of Evolution (1870), Huxley notes that investigations of "the extinct reptilian forms of the Ornithoscelida (or Dinosauria and Compsognatha) have brought to light the existence of intercalary forms between what have hitherto been always regarded as very distinct classes of the vertebrate sub-kingdom, namely Reptilia and Aves. Whatever inferences may, or may not, be drawn from the fact, it is now an established truth that, in many of these Ornithoscelida, the hind limbs and the pelvis are much more similar to those of Birds than they are to those of Reptiles, and that these Bird-reptiles, or Reptile-birds, were more or less completely bipedal. When I addressed you in 1862, I should have been bold indeed had I suggested that palæontology would before long show us the possibility of a direct transition from the type of the lizard to that of the ostrich. At the present moment, we have, in the Ornithoscelida, the intercalary type, which proves that transition to be something more than a possibility; but it is very doubtful whether any of the genera of Ornithoscelida with which we are at present acquainted are the actual linear types by which the transition from the lizard to the bird was effected. These, very probably, are still hidden from us in the older formations." He was an early proponent of the idea, which has received respect recently, that dinosaurs had bones and organs like those of birds and may have been warm-blooded as well.
Papers of his in the present library exemplify his paleontological interest in the evolution of reptiles and birds, particularly in his original notion that larks and other birds evolved from reptiles (though not from Archeopteryx).
In the last of these, he fires at his most frequent target, Professor Owen, in a footnote: "Prof. Owen evidently attached no weight to the fact as indicating any affinity of the Dinosauria with birds, as in his 'Report on British Fossil Reptiles,' 1861, p. 102, he says that 'the Reptilian type of structure makes the nearest approach to Mammals in the Dinosauria. '" He even disapproved of Owen's invention of the word "dinosaur," writing in On the Classification of the Dinosauria: "Even in point of etymological appropriateness, the term 'Dinosauria' is no more fitting for reptiles of which some are small, than 'Pachypoda' is for reptiles of which some have slender feet; but as Von Meyer's name has never obtained much currency, it may be well to allow justice to give way to expediency, and to retain the name of Dinosauria for those reptiles which agree in all the most important and characteristic parts of their structure with Megalosaurus and Iguanodon."
In On Our Knowledge of the Causes of the Phenomena of Organic Nature, six lectures to working men in 1863, Huxley had noted the paleontological importance of a discovery in the Connecticut Valley of dinosaur footprints. When he visited the United States in the fall of 1876, he again alluded to reptilian and avian evolution in his Lectures on Evolution, and was delighted to be taken by Professor Marsh to see the comprehensive fossil collection Marsh had deveoped at Yale University. Other papers relevant to his paleontological investigations of this time are On the Evidence as to the Origin of Existing Vertebrate Animals (1876) and Pedigree of the Horse (1876).
Herpetology includes (despite its etymology) the study of amphibians as well as reptiles. Huxley was an active and very productive paleontologist in the study of fossil amphibians, especially Labyrinthodont. Investigation of "carboniferous corpses" in Ireland and elsewhere led him to invent eleven genera of labyrinthodontsNovember 27, 1865. In a letter to Parker of 1874, Huxley noted that he was benevolent to all the world because he possessed a number of live and dead specimens, and looked forward to getting lots of frogs and toads. "We will work up the Amphibia as they have not been done since they were creaI mean evolved." An article presumably for the laity, but hard enough for herpetologists, is Amphibia in the Encyclopedia Britannica.
In his New York Lectures on Evolution and elsewhere he described the fossil remains of horses as well as of dinosaurs. See § 16. Miltonic Hypothesis: Genesis. His most dramatic and subversive exploration into paleontology was not that linking reptiles with birds or horses with other mammals, but linking human beings with apes § 7. Bobbing Angels: Human Evolution.