544 The Dipnoan Brain. | [June 
L. Woolman has a note on the “ Oriskany Sandstone in Ly- 
coming County, Pa.,” in the Proc. Acad. Nat. Sct. Philad., p: 296, 
September, 1886. 
THE DIPNOAN BRAIN." 
BY BURT G. WILDER. 
HIS paper includes an account of the brain of Ceratodus 
(Neoceratodus Gill), substantiated by photographs and prep- 
arations of three unusually well-preserved specimens in the Mu- 
seum of Cornell University; an admission of the writer’s own 
earlier errors in respect to the brains of “ fishes,” especially in 
disregarding the membranous portions of the ccelian parietes; a 
criticism of Huxley’s paper in the Zool. Soc. Proc., January 4, 
1876 (the later paper of Beauregard does not discuss the structure 
of the brain); a tabular statement of the resemblances and dif- 
ferences between the Dipnot and other groups, particularly the 
Plagiostomes and Amphibia; a reiteration of belief (Am. Assoc. 
Proc., 1875, 189) in the paramount value of cardiac and enceph- 
alic chiarite for the discrimination of more comprehensive 
groups; a reference to the morphological significance of the 
aula or mesal division of the prosoccele; a list of points requir- 
ing further investigation. 
The brain of Ceratodus agrees with that of Protopterus (as de- 
scribed and figured by Fulliquet in the Recueil Zool. Suisse for 
- 1886, and as seen in a recent dissection by the writer) in the im- 
portant point that zhe prosencephal consists mainly of a pair of 
large lobes whose cavities ( proceles or “lateral ventricles’) are 
connected only by a comparatively small aula, as in Amphibia and 
the higher vertebrates. Unlike Protopterus, however, between 
the dorsal parts of these lobes there is a Jong and thick supraplex, 
which, through an interruption of the proper nervous parietes 
for nearly the whole length, sends into each lobe a prolongation 
covered, like all plexes, by the lining endyma. In mammals, 
ofa paper On the Brain of Ceratodus, with Remarks upon Classifica 
General 
* Abstract 
tion and the Morphology of the Vertebrate Brain,” read, by invitation, biter 
_ the National Academy of TO ator 1887. 
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