332 
The . I in c rim u (iiniliiqi.fl . 
May, 1894 
and the dorsal or marginal expansion producing the trumpet 
form of the body whorl in ('. curiosa much abbreviated. Mr. 
Whitfield suggests the resemblance of the shell to a sinistrally 
coiled Infundibulum. In the latter of Whitfield's species the 
broad dorsal expansion which produces the conical form in 
the typical Clisiospira is wanting, and the shell has more the 
appearance of a reversed Capulus than a reversed Cuhjptrwa. 
As suggested by the author himself, it probably will prove to 
be a representative of Lindstrom's genus Onychochelhts. 
In a fauna of the later Devonian in New York (Intumes- 
cens fauna) occur two species of conical shells whose exter- 
nal similarity to forms of Ant<><hh<s and Clisiospira is at once 
striking. One of these has been found in the concretions of 
the Naples beds in the Whetstone gully, Honeoye lake, asso- 
ciated witli Clymenia neapolitana, Goniatites intumescens, etc., 
the other in the Styliola layer of the Genesee shales on Can- 
andaigua lake.* The former is a shell of about the same 
proportions as the species of Autodetus described above, while 
the latter is of considerably larger size. Both and all are 
characterized by the fine, irregular, concentric lineation of 
the external surface, the regularly conical form, and there is 
almost an agreement in the complete obscuration of the ex- 
ternal suture. The Naples species, however, hears a minute 
external spiral at the apex, which shows no evidence of at- 
tachment, and while the shell 
from the Styliola layer is broken 
at the apex, both prove to be 
dextrally. rather than sinistrally 
coiled shells. Upon examination 
of the shell substance it is found 
to be thin throughout, without 
evidence of columella or testa- 
ceous thickening in any part. 
In the shell whose apical por- 
Fi«s. 10, 11. Lateral and apical views 
uf protocalyptraea marshalli. x:t. 
Fig. 10 slightly restored at the mar- 
tfiu. Naples beils, Honeoye lake, N. V 
"The writer has shown in various papers thai in Ontario and the. ad- 
joining counties the earliest appearance of the Inlninesceiis fauna is in 
the limestone occurring at aboul the middle of the Genesee shales, 
known as the Styliola layer: disappearing from this region during the 
interval of the deposition of the upper portion of the shales, it reappears 
abundantly developed in the Naples beds above. (See Hull. IT. S. Geol. 
Survey, No. Hi. 1884: Neues Jahrb. fur Mineral., vol. i. 1891; Amkki. an 
Geologist, vol. vm, pp. 86-105, Aug., 185)1.) 
