THE FOSSIL AVIFAUNA OF THE 
3(»5 
were in one lot ; all the coracoids of Grebes in another ; all tlie coracoids of Cormo- 
rants in another, and so on for all the other bones of the skeleton, and for the dif- 
ferent groups of birds to which they had belonged. 
Now by carefully studying all the broken bones and fragments, and the use of 
splints and strong glue a good number of the fractured bones w'ere restored. In 
some instances they were made complete, wdiile in others so nearly* so as to make 
specific diagnosis certain. With such work every piece, however small, is of value, 
and thi’ows light upon the solution of any problem under consideration. EsiHJcially 
is this the case in the long bones of Waders and Herons. 
After the collection had been gone over a number of times and studied up to 
this point, two lots of specimens were set aside irot to be used again. One of 
these contained the fossil bones of vertebrates not birds, and the other a ma.xs ol 
broken fossil bird bones too fragmentary for any fui’ther use. 
Taking the Pygopodes now in hand, I placed all the coracoids, for instance, in 
one lot that seemed to belong to the same species, then all the tarso-metatai-si in 
another lot, and so on for all the bones of the skeleton. Group after group was 
treated in this way, until the entire recognizable part of the collection had lx*en 
gone over again. In one or two instances this actually showed exactly how many 
species were represented in a particular group. For e.xample, supposing in thus 
assorting them I found nine kinds of coracoids of Ducks, then upm assort- 
ing the ulnrn of those birds, I also found nine dillerent kinds ; then nine 
kinds of carpo-metacarpi and so on until the Duck bones were all as.sortcd into 
specific lots. It would be fairly good evidence that 1 had nine species of fossil 
Ducks before me. Group after group was thus studied and their lx)nes classified, and 
when this had been accomplished it resulted in another small lot of Injiies Ixung 
set aside as “ doubtful ”. Some of the latter were used again, but after all 
the species had been either identified or named as extinct and new siK'cies thei-e 
still remained a small lot of bones set aside as ‘‘ not identified which lot must 
remain until more material is collected at Silver Lake for additional light to 
determine them. 
After the collection had been treated in the manner tlius descrilxnl I was able 
to undertake the determination of the specific forms it represcmted, and I at once 
passed to a consideration of the Pygopodes. 
PYGOPODES. 
Prof Cope found three Grebes represented in the collection and gave it as hi.s 
opinion that they were Podiceps occidentalis Lawr., Podiceps californints I leenm, and 
Podilynihis podiceps Linn, and of the first named he said that one of the most 
abnndant species was a grebe, which I could not distinguish from the one so com- 
monly seen in Silver Lake, {Podiceps occidentalis Lawr.”-) 
^The Amer. Nat., November, 1889, pp. 978 and 980. 
52 JOUR. A. N. S. PHILA., VOL. XI. 
