874 
There is a traditional view that these 
animals were ponderous and sluggish. This 
view may apply in a measure to Bronto- 
In the case of Diplodocus it is cer- 
tainly unsupported by facts. 
As compared with the Crocodilian or 
Cetacean type, the axial skeleton of Diplo- 
docus is a marvel of construction. It is a 
mechanical triumph of great size, lightness 
and strength. Judging by the excessive 
rugosity of the vertebra and limbs, the 
powerful interspinous ligaments attached to 
the pre- and post-spinal laminee, the back- 
wardly directed rugosities at the summits 
of the diapophysial laminge in the dorsals, 
and of the postzygapophysial lamine in the 
caudals, the animal was capable not only of 
powerful but of very rapid movements. In 
contrast with Brontosaurus it was essentially 
long and light-limbed and agile. Its tail 
was a means of defense upon land and a 
means of rapid escape by water from its 
numerous carnivorous foes. Its food proba- 
bly consisted of some very large and nutri- 
tious species of water-plant. The anterior 
claws may have been used in uprooting such 
plants, while the delicate anterior teeth were 
employed for prehensile purposes only. The 
plants may have been drawn down the throat 
in large quantities without mastication, 
since there were no grinding teeth whatever. 
It is only by some such means as this that 
these enormous animals could have obtained 
sufficient food to support their great bulk. 
Henry FarrrirELD OsBORN. 
Saurus. 
THE NOMENCLATURE OF THE NEW YORK 
SERIES OF GEOLOGICAL FORMATIONS. 
THE prime outcome of the work of the 
four geologists, Mather, Emmons, Vanuxem, 
Hall, engaged upon the original survey of 
the State of New York, was the promulga- 
tion of a series of terms designating and 
classifying the rock formations. Many ofthe 
terms adopted in the final reports issued in 
1842-1843 had been previously introduced 
i 
SCIENCE. 
[N.S. Vo. X. No. 259. 
in the annual reports of one and another 
of the geologists, but that finally announced 
was the mutual agreement of the four. 
Tradition and contemporary record have 
given us some evidence that differences of 
Opinion as to the merits of various terms 
erected during the progress of the survey 
were not wholly reconciled by the final pro- 
nouncement which rejected a goodly num- 
ber of provisional names. It was clearly 
the purpose of the geologists to institute 
and defend a classification of the older 
rocks, the stratigraphic units of which were 
to be of approximately equal value. In 
several instances subdivision of such units 
was recognized; thus Hall and Vanuxem 
especially added the term group to some 
units as indicative of a minor subdivision 
of the strata. Emmons avoided this term 
wholly and Mather seldom employed it. 
The geologists also made use of a broader 
assemblage of the units into associations 
termed by some of them growps, by others 
divisions. These were four in number, 
namely, beginning at the bottom : Champ- 
lain, Ontario, Helderberg, Hrie, and a fifth, 
Catskill, was employed by Mather. There 
was pretty uniform agreement in the use 
of these broader terms and such slight dis- 
crepancy as became apparent in their appli- 
cation was no more than an expression of 
imperfect knowledge and of personal equa- 
tion. It was a genuine misfortune to the 
New York nomenclature that disturbed and 
drove out these terms which are supremely 
adapted to the unequaled paleozoic suc- 
cession from which they emanated. In 
many respects they meet the actual condi- 
tions far more satisfactorily than the EKuro- 
pean terms which we are now carrying. 
They are entitled to respect for their ven- 
erableness and, where consistent with the 
present state of knowledge, to recognition 
for their merit. 
It will be observed that the classification 
proposed by the four geologists was wholly 
