214 SCIENCE PROGRESS 



cleft. Pocock was therefore right when he challenged the 

 validity of the association of the pre-orbital or malar fossa with 

 a face-gland. Dr. Gregory's Memoir is illustrated with a number 

 of very beautiful figures. 



As touching the broad outlines of the evolution of the horse, 

 or the elephant, we are all in agreement ; but it is otherwise 

 where interpretation is concerned with tables of descent. The 

 tendency to-day is to break up the phylogenetic sequences 

 which have been generally accepted, and to multiply the number 

 of hypothetical ancestors belonging to a still more remote 

 past. These, when found, are to link up, once more, the now 

 dismembered ancestral tree. 



A case in point is furnished by Prof. Henry Fairfield Osborn 

 in discussing the Evolution, Phylogeny, and Classification of 

 the Proboscidea (American Museum Novitates, No. i, 192 1). 

 In the space of a few pages the author has contrived to provide 

 material for argument for a very long time to come : for many 

 of his conclusions run counter to the generally accepted beliefs 

 on this theme. But even those who venture to differ from him 

 will find in this essay a stimulus to further research. 



In a second paper, on the First Appearance of the True 

 Mastodon in America {American Museum Novitates, No. 10, 

 1 921), Prof. Osborn shows that this animal reached America 

 during the early Pliocene, as a derivative form of Mastodon 

 tapiroides ajnericanus, of the lower Pliocene of Hungary. It is 

 represented in America by two species here described for 

 the first time — M. matthewi, from Sioux County, Nebraska {Pro- 

 camelus Hipparion Zone), and M. merriami, from the Thousand 

 Creek formation, Humboldt County, Nevada. 



Dr. W. K. Gregory's fine " Review of the Evolution of the 

 Lachrymal Bone of Vertebrates, with Special Reference to that 

 of Mammals " (Bidl. American Museum of Natural History, 

 vol. xlii) was not published till December last. It will be read, 

 and eagerly read, by zoologists and palaeontologists alike. 

 His survey embraces the whole of the vertebrates from the 

 fishes upwards, but it is too long to be briefly summarised. 



A fossil marsupial skull of remarkable interest is described 

 by Dr. H. D. Longman, the Director of the Queensland Museum, 

 in the Memoirs of the Queensland Museum, vol. vii, 1921. The 

 surprising feature of this skull lies in the enormous and out- 

 standing jugals, which, it is suggested, formed " cheek-pouches." 

 Whether this interpretation is correct is doubtful. A further 

 study of this skull, and a comparison with that of Diprotodon, 

 may enable this point to be settled later. For the moment, 

 at any rate, the skull of Euryzogoma forms a notable addition to 

 the list of instances of " Hypertely," so interesting from the 

 evolutionary point of view. 



