SEPTEMBER 25, 1902] 
limitations of our departments. I quote from an official report 
in alluding to ‘‘comparative anatomists, or biologists, as they 
call themselves,” and I but cite the words of an eminent scientific 
friend, in referring to biology and botany as coequal. In 
endeavouring to get rid of this prevailing error, let it be once 
more said that the term “biology” was introduced at the 
beginning of the nineteenth century by Treviranus and Lamarck, 
and that in its usage it has come to signify two totally distinct 
things as employed by our continental contemporaries and our- 
selves. By ‘‘ Biologie” they understand the study of the 
organism in relation to its environment. We, following 
Huxley, include in our term biology the study of all phenomena 
manifested by living matter; botany and zoology; and by 
morphology we zoologists mean the study of structure in all its 
forms, of anatomy, histology and development, with palzeon- 
tology—of all; that is, which can be preferably studied in the 
dead state, as distinct from physiology, the study of the living in 
action. Comparative morphology, the study of likeness and un- 
likeness, is the basis of our working classifications, and it is to the 
consideration of the morphological method, and the more salient 
of its recent results, that I would now proceed, in so far as it 
may be said to have marked progress and given precision to our 
ideas within the last eight-and-twenty years. I would dealin the 
main with facts, with theories only where self-evident, ignoring 
_ that type of generalisation to which the exclusive study of 
embryology has lent itself, which characterises, but does not 
grace, a vast portion of our recent zoological literature. 
To the earnest student of zoology, intent on current advance, 
the mental image of the interrelationships of the greater groups 
of animal forms is ever changing, kaleidoscopically it may be, 
but with diminishing effect in proportion as our knowledge 
becomes the more precise. 
Returning now to American paleontology, we may at once 
continue our theme. In this vast field, expedition after expedi- 
tion has returned with material rich and plentiful ; and while, 
by study of it, our knowledge of every living mammalian order, 
to say the least, has been extended, and in some cases revolution- 
ised, we have come to regard the Early Tertiary period as the 
heyday of the mammals, in the sense that the present epoch is 
that of the smaller birds. No wonder then that there should 
have been discovered group after group which has become 
extinct, or evidence that in matters such as tooth-structure there 
is reason to believe that types identical with those of to-day 
have been previously evolved but todisappear. To contemplate 
the discovery of the Titanotheria, the Amblyopoda, the Dino- 
cerata, with their strange diminutive brain, chief among the. 
heavier ungulate forms, is to consider the Mammalia anew ; and 
when it is found that among late discoveries we have (1) that of 
a series of Rhinoceratoidea, which though not yet known to 
extend so far back in time as the primitive tapirs and horses 
are complete as far as they go; (2) that among the 
Ruminants we have, in the Oreodontide of the American 
Eocene, primitive forms with a dentition of forty-four teeth, an 
absence of diastemata, a pentadactyle manus, a tetradactyle pes 
with traces of a hallux, and, as would appear from an example 
of Mesoreodon, a bony clavicle, such is unknown in any later 
ungulate, we are aroused to a pitch of eager enthusiasm as to the 
outcome of labours now in hand ; for, as I write, there reaches 
me a letter to the effect that for most of the great vertebrate 
groups, and not the mammals alone, collections are still coming 
in, each more wonderful than the last. 
In the extension of our knowledge of the Ancyclopoda, an 
order of mammals named efter the Ancylotherium of Pikermi 
and Samos, which occur in the Early Tertiary deposits of 
Europe, Asia, North America and abundantly in Patagonia, we 
have been made aware of the existence of genera whose salient 
structural features combine the dentition of an ungulate with the 
possession of pointed claws, believed to have been retractile 
like those of the living cats. Conversely to these unguiculate 
herbivores, which include genera with limbs on both the artio- 
and perisso-dactyle lines, there have been found, among the so- 
called Mesonychidz, undoubted primitive carnivores, indications 
of a type of terminal phalanx seal-like and approximately non- 
unguiculate ; from all of which it is clear that we have in the 
rocks the remains of forms extinct which transpose the correla- 
tions of tooth and claw deducible from the living orders alone. 
Further, among the primitive pentadactyle Carnivora we meet, in 
the genus Patriofelis, with a reduction of the lower incisors to 
two, and characters of the fore-limb which, with this, suggest 
the seals. It is, however, probable that these characters are in 
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52 
no way indicative of direct genetic relationship between the two, 
for, inasmuch as these animals were accustomed to seek their 
food in the water of the lake by which they dwelt, their seal- 
like characters may be but the expression of adaptation to a 
partially aquatic mode of life—of parallelism of modification 
with the seals and nothing more. 
Early in the history of their inquiry, our American confréres 
recorded from the Pliocene the discovery of camel-like forms 
possessed of a full upper incisor dentition; for example, the 
genera Protolabis and Ithygrammodon ; and now they have 
arrived at the conclusion that while the camels are of American 
origin, one of their most characteristic ruminants, the Prongbuck 
(Antilocapra), would conversely appear to be the descendant of 
an ancestor (Blastomeryx) who migrated from the old world. 
Sufficient this concerning the work in mammalogy of the 
American palzontologists. While we return them our devout 
and learned admiration, we would point out that the brilliance 
of their discoveries has but beclouded the recognition of equally 
important investigations going on elsewhere. In Argentina 
there have proceeded, side by side with the North American 
explorations, researches into the Pleistocene or Pampa fauna, 
which in result are not one whit behind, as has been proved by 
the recognition of a whole order of primitive ungulates, the 
Toxodontia, by that of toothed cetaceans with elongated nasals, 
as in the genera Prosqualodon and Argyrocetus, and of sperm 
whales with functional premaxillary teeth, viz. Physodon and 
Hypocetus, to say nothing of giant armadillos and pigmy 
glyptodons. 
It will be remembered by some present that, from Patagonian 
deposits of supposed Cretaceous age, there was exhibited at 
our Dover meeting the skull of a horned chelonian Meiolania, 
which animal, we were informed, is barely distinguishable from 
the species originally discovered in Cook’s Island, one of the 
Society group, and which, being a marsh turtle highly 
specialised, would seem in all probability to furnish a forcible 
defence for the theory of the Antarctic continent. But more 
than this, renewed investigation of the Argentine beds by the 
members of the Princeton University of North America have 
recently resulted in collections which, we are informed, seem 
likely to surpass all precedent in their bearings upon our current 
ideas, not the least remarkable preliminary announcement being 
the statement that there occurs fossil a mole indistinguishable, 
so far as is known, from the golden mole (Chrysochloris) of 
South Africa. 
Before I dismiss this fascinating subject, let me disarm the 
notion, which may have arisen, that the paleontological work 
of the old world is done, Far from it! Even our American 
cousins have to come to us for important fossil forms ; as, for 
example, the genus Pliohyrax of Samos and the Egyptian 
desert, while among the rodents and smaller carnivores there are 
large collections in our national museum waiting to be worked 
over afresh. 
If one part of the globe more than another is just now the 
centre of interest concerning its vertebrate remains, it is the 
Egyptian desert. Here there have recently been found the 
bones of a huge cetacean associated, asin South America, with 
those of a giant snake, one of the longest known, since it must 
have reached a length of thirty feet. There also occur the 
remains of other snakes, of chelonians of remarkable adaptive 
type, of crocodilians, fishes and other animals. Interest, 
however, is greatest concerning the Mammalia, which for 
novelty are quite up to the American standard, as with an upper 
and a lower jaw of an anomalous creature, concerning which we 
can only at present remark that it may be a marsupial, or more 
probably a carnivore, which has taken on the rodent type in a 
manner peculiarly its own. Important beyond this, however, area 
series of Eocene forms which more than fill a long-standing gap, 
viz., that of the ancestors of the Elephants and Mastodons, 
which hitherto stopped short in the Middle Miocene of both old 
and new worlds. As represented by the genus Meeritherium, 
they have three incisors above and two below, of which the 
second is in each case converted into a short but massive tusk. 
An upper canine is present, and in both upper and lower jaws a 
series of six cheek-teeth, distinct and bunodont in type. In the 
allied Barytherium, of which a large part of the skeleton is 
known, the upper incisors were presumably reduced to two, 
the tusks enlarged, with resemblances in detail to the Dino- 
ceratan type. 
So far as these remains are known, they appear to present in 
their combined characters all that the most ardent evolutionist 
