158 ON THE OEGANS OF GENERATION, &C. 
but it is evident that this measurement is not to be depended 
on. It terminates anteriorly on either side, by four white, 
conical elastic papillae, resembling nipples. These may be 
considered as the terminating points of a double glans, 
though this, during the relaxed state, is by no means very 
distinct. When the penis is cut across, or opened into, it 
is found to possess a structure resembling the usual corpora 
cavernosa^ and to be almost entirely composed of numerous 
vessels of comparatively large caliber. The parietes are 
dense and strong. 
It will no doubt be expected of me, by many of the 
gentlemen who have done me the honour to listen to this, 
and to the preceding memoirs, that I should explain how 
the anatomy of parts apparently easily made out, should 
have been so singularly misunderstood by the French ana- 
tomists ; and how, after the observations of Sir Eve hard 
Home, which partly coincide with the above, the same er- 
rors should have been repeated in the " Regne Animal^'' 
published so late as 1817 ; that is, fifteen years after the 
publication of Sir Everard Home's observations in the 
Transactions of the Royal Society of London. The an- 
swering these questions I consider as a duty I owe as well 
to the Society before which I read this memoir, as to the 
distinguished naturalist who intrusted me with the dissec- 
tion, and who, now for a long time, with unexampled libe- 
rality, has forwarded, to the utmost of his power, my re- 
searches into comparative anatomy. 
To the first question I reply, that the account of the 
anatomy of the organs of generation in the male Ornitho- 
rynchus, contained in the fifth volume of the Jnatomie 
Comparee, page 104., could not have been taken from any 
dissection by the immortal author of that work, but from 
one performed by an assistant. I shall therefore omit 
copying it into this memoir, well aware that it will not re- 
