ii6 'Prof . Amos H. Worthen — Ulrich. 
these shells were preserved in the limestones and shales of his 
locality, and he worked diligently to learn sometliing of their 
history and of the specific characters of the animals to which 
they once belonged. 
This task was one of great difficulty since the only works he 
had been able to obtain that contained any account of fossils 
were Dr. Mantell's "Medals of Creation" and " Wonders of 
Geology," both published in England. These threw but little 
light upon the specimens he had gathered, but they gave him 
an insight into the manner in which the rocks had been formed 
and how the remains of living forms came to be preserved in 
them. 
His collection grew apace and soon began that extensive sys- 
tem of exchanges with other scientists that gradually not only 
furnished him with the information so much desired, but also 
made both his cabinet and knowledge valuable enough to com- 
mand the attention of leading eastern geologists. Many of his 
fossils were loaned by Prof. James Hall and illustrated in the 
report on the palieontology of Iowa. Prior to this time (it was 
in February, 1S51 ) a law had been passed authorizing a geolog- 
ical survey of Illinois, and two years later an appropriation 
was made to carrv it out, and Prof. Norwood appointed state 
geologist. Prof. Worthen did some work under him but soon 
(in 1855) engaged in more active work in Iowa under Prof. Hall. 
In the meantime the work in Illinois languished; although five 
3'ears passed, no report was made and when on March 22nd, 
1858, Gov. Wm. H. Bissell placed in the hands of Prof. Wor- 
then his commission as state geologist, nothing of prior work 
came to his hands save a report by Prof. Norwood on the lead 
mines of Harden county and the field notes of his assistants. 
On taking charge of the survey Prof. Worthen at once began 
earnest and active field work, in prosecuting which he has proba- 
bly carried a greater bulk and weight of geological specimens 
than any other geologist of his day. He also secured for the 
work the assistance of some of the ablest specialists — notably 
Prof. Leo. Lesquereux in palaiobotany and Carboniferous strati- 
graphy, Dr. J. S. Newberry and Prof. Orestes St. John in 
vertebrate palaeontology, Prof. F. B. Meek and Mr. E. O. Ulrich 
in invertebrate palasontology, Prof. J. D. Whitney in mineral- 
