330 The Critics of Evolution. [ May, 
bones are not distinguishable from those of recent species.” 
Thus the bones of the fossil beaver and wolf cannot be distin- 
guished from those of the recent, while they are also associated 
with the remains of an extinct fossil elephant, horse and llama. 
The species derived from the cave formations of the Eastern States, 
which Cope names the Megalonyx beds, also present many in- 
stances of extinct species mixed with the remains of those repre- 
sented by the living ground-hog, porcupine, hare and rabbit and 
from which they cannot be distinguished. 
In further illustration of this error of Agassiz, we may also cite 
the continued existence of the Lizgule, formerly included among 
mollusks, but now shown: to be allied more closely to worms. 
The Lingule were numerous and important in earlier geological 
ages and have been continued almost from the dawn of life and as 
they exist in the primordial “are scarcely to be distinguished as 
even Prof. Dawson acknowledges! from those of the members 
of the genus which still live.’ The original Limgu/e were re- 
markable for the presence of phosphate of lime in their shells, a 
peculiarity not found in the shells of mollusks generally, which 
are hardened by the presence of carbonate of lime. The modern 
Lingule present the same peculiarity and exhibits the wonderful 
persistence with which they adhere to the original type. 
It was the merit of Agassiz that he drew especial attention to 
the remarkable parallelism between the embryonal and the palæ- 
ontological or the development through time and the development 
of organic species, genera and tribes, which is claimed as one of 
the strongest pillars of the theory of descent or of evolution. No 
one before had so distinctly stated as Agassiz did, that of verte- 
brate animals, fishes alone existed at first, that amphibians came- 
next, and that birds and mammals appeared only at a much later 
period, and moreover that among mammals, as among fishes, im- 
perfect and lower orders had appeared first, and more perfect 
higher orders at a later period. He thus showed that the palzon- 
tological development of the vertebrates was not only parallel 
with the embryonic, but also with the systematic development or 
the graduated series which we see everywhere is ascending from 
the lower to the higher classes, orders, &c. Haeckel. This doc- 
trine is explained quite simply and naturally by the doctrine of 
descent, or a historical succession, and without it, is perfectly in- 
1 &« The Story of the Earth and Man,” by J, W. Dawson. 1873. p. 4I- 
