1893.] On the Genera of the Dipnoi Dipneumones. 927 
apparatus will be found by making a proper study of the skin. 
Referring to the occurrence of taste-buds in the Lepidosiren 
annectens, Parker states that I have described somewhat similar 
organs on the palate of Ceratodus. As a matter of fact, the de- 
scription I gave applied to both Ceratodus and Protopterus, 
though I figured the organs from Ceratodus alone. I am 
pleased to see that Parker is able to confirm my own observa- 
tions in this respect. 
Hyrtl states that the intestinal canal of Lepidosiren paradoxa 
is slightly S-haped in the horizontal plane. r 
In Ceratodus forsterii and Lepidosiren annectens I found there 
was no indication of curvatures in the horizontal plane; but 
Parker states that he finds the gut in L. annectens slightly 
curved (S-shaped) in the vERTICAL plane, and hence that my 
statement that the alımentary tract in the Dipnoi is strictly 
parallel with the notochord is incorrect. : 
Even Parker's observations show the correctness of my state- 
ment, while he says, on page 215, * The alimentary canal ex- 
tends almost in a straight line from the mouth to the vent,” 
making no mention of curves. 
The sensory papilla which I found projecting asa finger- 
shaped process part way across the anterior narial opening in 
L. annectens, Parker was unable to detect. No histological ex- 
amination was made of this papilla, but I judged it to be tac- 
tile in function and from its location to serve as a guard to the 
entrance of the nasal chamber. 
Our author does not produce any evidence for the support 
of his change in the name of the URINARY BLADDER to that of 
the CLOACAL CÆCUM, and he adds nothing to our knowledge 
of either its structures or its functions, so that any comparison 
of this organ with the rectal gland of Elasmobranchs is entirely 
against the known morphological relations of the two organs. 
The rectal gland of Elasmobranchs is a diverticulum of the 
gut in close relation with the end of the spiral valve, while the 
urinary bladder of the Dipnoi is a pocket of the cloaca entirely 
foreign to the gut, since it lies outside of the rectal sphincter 
and in close relation with the openings of the kidney ducts. 
With regard to the LYMPHOID ORGAN of the mid-gut, which 
