Williams.] FAUNAL DISSECTION OF THE DEVONIAN. 91 
The species of the Waverly fauna collected and identified by Dr. Kindle are as 
follows: 
Table XXIV .—Tropidoleptus faunule as a colony in Chemung formation, Waverly, 
N. Y. (1462 B, U. S. Geological Survey), identified by E. M. Kindle ( 1902). 
1. Tropidoleptus carinatus 
a' 
1 Hamilton. 
2. Amboccelia umbonata 
a 
Marcellus-Chemumg. 
3. Rhipidomella vanuxemi 
c 
Cornif erous [Onondaga] -Hamilton 
4. Spirifer marcyi 
c 
Hamilton. 
5. Cypricardella bellistriata 
c 
Hamilton. 
6. Productella lachrymosa 
c 
Chemung. 
7. Delthyris mesicostalis 
c 
Ithaca-Chemung. 
8. Camarotcechia contracta 
r 
Portage- Waverly. 
9. Schizophoria cf. tioga 
rr 
Portage-Chemung. 
10. Leptodesma matheri 
rr 
Chemung. 
11. Glyptodesma erectum 
rr 
Hamilton. 
12. Pterinopecten sp. 
rr 
13. P. crenicostatus 
rr 
Chemung. 
14. Modiomorpha cf . concentrica 
rr 
Hamilton. 
15. Cyrtina hamiltonensis 
rr 
Up. Held., Ham., Portage, Chemu 
The commonly reported range by formations is given in the column on the right. 
In this faunule, it will be observed, the abundant and common forms are. with 
the exception of Productella, chiefly found in the Hamilton formation. 
Nevertheless, the faunule occurs in the rocks after the Spirifer disjunctus fauna 
has occupied the region in force with its typical development; thus showing that 
in time the two faunas were coexistent in separate areas in their normal bionic 
strength. That is to say, in the areas of their geographic metropolis, each fauna 
maintained its bionic equilibrium as expressed in frequency and dominance of 
species. 
The importance of this case of recurrence of the Tropidoleptus fauna is so great 
as to call for every precaution as to its verity. The intrinsic evidence of its 
Chemung horizon was not present in the Owego faunule. 6 There are no species 
there which might not occur as low as the Ithaca group. But the faunule col- 
lected at Waverly contains Delthyris mesicostalis with a distinctly strong median 
septum, which is wanting or very slightly developed in the specimens of the 
Ithaca formation; also a single specimen of Schizophoria tioga, nothing like 
-which is known in the typical fauna of the Ithaca formation. The Productella 
lachrymosa is not so strongly of the true lachrymosa type as to make it certain 
that it may not be an extreme variation of Productella speciosa. The leptodesmas 
are so variable that the form L. matheri is not conclusive of post-Ithaca stage. 
In my collections from the Waverly-Chemung cliffs, however, Tropidoleptus 
was discovered above the first appearance of Spirifer disjunctus and other typical 
members of the Spirifer disjunctus fauna. These facts are intrinsic evidence, 
therefore, that the combination of species, so much like the typical Tropidoleptus 
carinatus fauna of the Hamilton, is here present in a part of the rock section 
occupied in general by a typical Spirifer disjunctus fauna. 
The fact that the combination of species is the normal combination seen in the 
undisputed Hamilton formation shows that its equilibrium had not been dis- 
turbed, and therefore that the life history of the fauna of the Hamilton forma- 
tter, abundant; c, common; r, rare; rr, very rare. 
b Since the above was written I have examined the Owego locality and another locality wesl 
of Waverly and have proved beyond controversy that this recurrent Hamilton fauna occurs nol 
only well above Spirifer disjunctus, but several hundred feet above the base of the rocks along 
Chemung Narrows, constituting the typical exposure of the Chemung formation of Ball's Reporl 
of 1843. (Part IV, Geology New York State p. 252.).— H. 8, W. 
