8(S2 CONTRIBUTIONS TO NORTH AMERICAN, ICHTHYOLOGY IV. 
fork-tailed species, commonly referred to Aniiurm, the two bones are 
more or less close together; in some species apparently joined in the 
yonng, bnt separated in the adult; in others apparently slightly sepa- 
rated at the surface and joined under the skin. In but two species, 
furcaius and punctaUiH, is there a continnons bridge formed at all ages. 
In view of the comidete intergradation of this character, we have re- 
tained the name Amiurva for the species with truncate caudal and the 
interspinal and sui)raoccipital wholly se])arate, and Ictalnrus for those 
with forked caudal and the two bones in question joined or approxi- 
mated. The only other alternative, and a not unreasonable one, is to 
refer all these species to one genus, Ictalvrus. 
On page 108, instead of Ictalurus lacustris, read: 
806. I. iiig^rici&QSS (Le S.) Jor. 
The ‘■‘■Gadus lamstris^^* (Wall). Artedi, Pise. 1792, 144) can hardly 
be identified with any fish. 
Page 110. To the description of Arhift fells, the following may be 
added : 
Bauds of palatine teeth large, not prolonged backward over the 
pterygoid region ; fontanelle prolonged backward in a narrow groove; 
occipital process long, narrow, keeled. Pectoral rays I, 9. 
Arius eqnestris B. & G., is not distinct from A. fells, and should lie 
erased. 
Page 111. Instead of Plectospo7idyli read Order L. Eventognathi. 
The latter name is unobjectionable, and has priority of date. 
Page 113. We do not believe that IcHobus, Bubalichtliys, and Carpi- 
odes can be maintained as distinct genera, and think it preferable to 
unite the three under the earliest name, Ictiohus. In its dentition, 
Tctiohus is intermediate between Carpiodcs and Buhalichthys, and in 
structure of month Buhalichthys stands between the others. 
We have examined the original manuscript note-book of Eafinesque, 
containing the descriptions which were afterwards printed in the Ich- 
thyologia Ohiensis. In this book is a drawing of his ^^Ictiohtts hubalus,^' 
^ It is described as follows: 
“ Gadus laciistris, Americaiiis Mathemeg, Auglis Land Cod, Pennant, Arot. Zool. 
Introd. p. 191. Corpus tripedale, snperne sub spadiceuni, inferne griseuni; cirri tres 
in mandibula inferiore, quorum medius longitudiue duos alios vincit.” 
The “Mathemeg or Land Cod” of Pennant is said by Richardson to be a cat-hsh, 
and it may have been /. nigricans, but the description is wholly insnfficient. 
