Evening star., 1949-10-10
Migrotions Of Dinosaurs
Traced by PoIeontoIoqist
180,000,0O0- -Year-Old Tracks
Found in Connecticut Valley
Rv Thomas r. Henry

NEW HAVEN, Oct. 10-Dinosaurs Of
180,000,000 years ago used to go on great
southwark migrations-perhaps periodically.
Such is one of the findings of DR.. Richard
S Lull, retired Yale paleontologist, from a
lifetime study of the remains of these rep
tiles in the ancient Connecticut Valley
which extended from the Vermont line to
the present Long Island Sound. Even in
those days some sort of a river flowed
through it. Several locations very rich in
disosaur tracks have been found and tons
of material collected in the past century.
There are footprints of various sizes i'm
planted in the rocks which have hardened
out of the ancient valley mud. In almost
every case, DR.. Lull says. these footprints
are pointed southwestward. The ancient
valley evidently was not so much dinosaur
pasture as migration road from south to
north
Several levels of such footprints have
been found. These indicate that between
migrations enough time must have elapsed
for considerable sediment to form. Thus
they could hardly have been seasonal, like
the migrations of birds who are descendants
of the dinosaurs.
Covers Long Period.
The record of the reptiles covers millions
of years. Some of the footprints are hardly
as large as chicken tracks. Others have
total length of about Is feet The latter
must have been made by monsters weigh
ing up to so tons. There were doubtless
many different species, DR.. Lull says, but
it is difficult to say whether some of the
differences in size of footprints may not
have been due to the fact that adults were
accompanied in the great migrations by
young in various stages of growth. 1t is not
known how long was required for one OF the
ancient monsters to attain full growth
The whole episode in geological history
represented by the Connecticut Valley COL,
lections must have closed before the emerg-
ence of birds or mammals, DR.. Lull says.
There were still surviving, however. speci-
mems of the ancient amphibians, allied to
the salamanders of the present. who were
the first vertebrates to emerge on land and
from whom the great reptiles arose.
Between the orbits of Mars and Jupiter
are thousands of hurtling rocks which move
in orbits around the sun. These are the
minor planets. Within the last few years
some have been found which are between
the orbits OF Mars and the earth.
They vary in dimensions from fair-sized
boulders to masses of rocks-like Ceres,
Pallas, Juno and Vesta-several hundred
miles in diameter.
A 15-year study of these curious objects
Is uOW uedI lIlk 1Go Cllo 1lC4C. A1i A0oo' q
list of 20 of the brightest of these planetoids
was selected and in the intervening years
up to 1948 total Of 5000 photographs was
obtained. These pictures, secured by varl-
Gus observatories. showed the tiny celestial
objects in different parts of their orbits.
which could be calculated according to the
laws of gravitation. Now, according to Prof.
Dirk Brewer of the Yale faculty, all but
1000 of these photographs have been meas
ured and the positions determined with ac-
curacy.
The precise orbits Of the planetoids will
be Of considerable value to astronomers In
terested in fixing star positions and deter
mining distances within the solar system.
In another Yale astronomical project now
nearing completion the positions and proper
motions of approximately 100000 stars lying
in the range 80 degrees North to 80 degrees
South Of the celestial equator have been
catalogued. It includes all the stars In that
part of the sky between the fourth and
eighth magnitudes-all considerably below
visibility with the naked eye. Most Of the
visible stars are not included IN the great
catalogue. There are relatively few Of them
and their positions are easily fixed.
The catalogue, based on all recorded OBJ
servations, is expected to prove Of great
value in determining the relative motions
Of various swarms Of stars through the
heavens and in showing various systematic
errors In observations.