200 FreLpD CoLUuMBIAN MuseEuM—GEOLOGY, VOL. I. 
one species of which has been described by J. A. Allen* as a passerine 
bird of the family Fringillide, the other by E. D. Copey+ as a species 
of the order Gralle and tribe Limicole. 
In conclusion, the hope may be expressed that if any specimens 
of similar character are known they will be fully described, so that 
more evidence may be at hand to clear up the difficulties encountered 
in the study of this one. I have reports of the finding of at least two 
other petrified eggs at different times in the same region, but have 
been quite unable to verify the reports or see the specimens. A 
systematic study of the forms of eggs seems also desirable, so that in 
the future definite conclusions may be drawn regarding the order 
or family to which a parent belonged when an egg is the only relic of 
the parent to be obtained. 

* Bull. U. S. Geol. Surv. Terrs., 1V, 1878, p. 443, Pl. I. 
+ Rept. U. S. Geol. Surv. Terrs., Vol. III, Book I, p. 754, PJ. LIX. 
