Qrnilhorynchus of New South Wales. 379 
There is nothing more wonderful in the anatomy of the orni- 
ihorynclms paradoxus , than the structure of the poison-gland and 
spur. These organs, which had been previously altogether mis- 
understood, our author has shewn not to be very complex or 
difficult of dissection. The poison-gland, which is comparative- 
ly large, is situated on either side, almost immediately under the 
integuments, and over the loins and hip-joint ; it transmits a 
tube of comparatively large calibre, which, after running down 
the back of the thigh and leg, terminates in a small sack, deep 
in the hollow of the foot. From this another membranous tube 
arises, which passes into the spur, and penetrates to its extremity, 
which is open, to permit the escape of the poisonous fluid which 
has been secreted by the gland, and which is in this way con- 
veyed into the wounds inflicted by the ornithorynchus on other 
animals. The whole series of organs resembles, in a certain de- 
gree, the poison apparatus of serpents. 
The poison-gland is about an inch in length, and five-tenths 
of an inch in breadth. It is a conglomerate gland, i. e. made 
up of smaller ones, imbedded in a tissue of a different appear- 
ance, and which is probably cellular. It lies longitudinally with 
respect to the spine, covering many of the muscles which rotate 
the thigh, and may readily be found by merely removing the 
integuments, paimiculus carnosus , and a small quantity of 
loose cellular membrane, lying over the os mnommatum and 
hip-joint. An excellent engraving of these organs by Mr Lizars 
accompanies this memoir. 
The Second Memoir contains observations on the organs of di- 
gestion and their appendages, and on the organs of respiration 
and circulation. The author remarks, that these organs gene- 
rally have been described with extreme accuracy by preceding 
anatomists, and more particularly by Baron Cuvier ; so that he 
found it difficult, if not impossible, to add much that was novel 
to their descriptions. He thinks that certain rudimentary grind- 
ing teeth, placed anteriorly to the true ones, have been over- 
looked by some anatomists. A small parotid seems to exist im- 
mediately connected with the cheek-pouches; the maxillary 
gland w r as very distinct ; and its duct, which opens immediately 
under the tongue, was readily injected with quicksilver. The 
