8 
J. T. CUNNINGHAM. 
simply say that the interpretations of Kupffer and Henneguy 
are still more unsatisfactory than Balfour’s and need not he 
considered. I hope I have shown in this paper that the view 
advocated by Henneguy and myself is the one which gives the 
true morphological meaning of Kupffer’s vesicle, and places it 
on the same basis as the cavity of the canal of the neurochord 
and of the otocyst in the Teleostean. 
I have arrived at this view quite independently, and flattered 
myself I was the first exponent of it. I find M. Henneguy has 
anticipated me by four years. I hope my support of the view 
will help to gain it the acceptance which so great an authority 
as Agassiz has denied it. 
There is one more question to be considered. Has the vesicle 
any physiological importance in the process of actual develop- 
ment? I think not; the intestine is formed in the anterior 
part of the body without the aid of such a cavity, and I think 
it is a true rudimentary structure which has persisted in spite 
of the modifications in the development of the Teleostean 
ovum, by reason of the strong tendency to perpetuate itself of 
a structure so fundamental in the primitive stages of evolution 
as the gastrula-cavitv. 
Remarks on General Vertebrate Morphology. 
Ever since I became acquainted with the theory which 
regards the Vertebrate as a worm turned on its back I have 
been more and more convinced of its fundamental truth. Of 
this theory Dohrn has been for years the most brilliant and 
most profound exponent and investigator, and although he has 
had, and may have again, occasionally to retrace his steps, he 
has won for us a point of vantage from which we may look 
back with clear view on the historical evolution of the Verte- 
brate organization. Mr. Sedgwick and his school have not 
embraced this theory ; yet one point in Mr. Sedgwick’s paper 
published in this Journal, January, 1884, will, in my opinion, 
do a very great deal towards completing the Dohrnian hypo- 
thesis. The point I refer to is the stress laid on the fact that 
