492 DR DAVY’S FRAGMENTARY NOTES ON THE 
upwards, and in that of the cloaca downwards, yet they are capable of holding a 
fluid, of which a certain quantity has always been found present, associated with 
the contained ova and their embryos. ‘These cavities, at least in the early period 
of gestation, have been found to communicate with the cloaca by two openings 
close to the papilla, in which is the common passage from two urinary bladders. 
Whether these openings do not become one at a more advanced period, I am 
doubtful. The figures in Plate XXII., from rude sketches with the pen made 
from nature, will help to give some idea of the several parts.* 
The first specimen examined was procured on the 30th August. Each uterine 
cavity was found to contain two ova with an embryo attached to each by an um- 
bilical cord,+ in the midst of much transparent colourless fluid, without any traces 
of a common enveloping membrane. The ova were large; each weighed about 2: oz. 
They consisted entirely of yolk, and, like those of the torpedo, they had two mem- 
branes, one internal, very delicate and transparent, of little more consistence than 
that of the albumen ovi of the fowl, but thickening towards and in the cord, the 
other internal and vascular. The embryos were all small, and of about the same 
size.| The branchial filaments were very short, and of a bright red colour; the 
eyes large and projecting; the mouth and gullet very large; the stomach very 
small; the intestine large and empty; the liver large. 
On the 31st of the same month another specimen was procured. Three ova, 
with embryos, were found in one uterine cavity; two in the other. They were 
nearly in the same stage of development as the preceding. One egg with its 
embryo weighed 33 oz.; the embryo, 22 grs.; another embryo, 17 grs. The 
former measured 1°7th inch in length, -45 inch in width. Some yolk was 
found in its intestine. The branchial filaments of both were about the same 
length as the preceding. The other eggs were not weighed; their membranes 
were so delicate that they broke in the attempt. The oviducts entire, including 
the uterine cavities and their contents, weighed 223 oz.; emptied of their con- 
tents their weight was 12 oz. and 29 grs. Now, supposing the weight of all 
the five eggs to be nearly the same, the weight of the fluid in both cavities would 
be about 41 0z. The cavities differed from the preceding, in being distinctly 
vascular. 
On the 12th September, a female fish was examined that weighed 6 lbs. An 
embryo was found in each uterine cavity, and attached to one of the ovaries a 
* Fig. 1. The oviducts expanding into a uterine cavity. Fig. 8. Kidney and urinary bladders. 
+ I use this term for the sake of convenience in its ordinary sense, and not being aware of any 
sufficient reason for discontinuing it, seeing that it performs the same part as the umbilical cord in the 
mammalia, connecting the embryo with its source of nourishment: moreover, a mark remains of it, 
denoted by a depression, after its removal by absorption, which may be called an umbilicus. This 
at least I have seen in the young torpedo.—See my “ Researches Physiol. and Anat.,” plate vii. fig. L., 
in which it is shown. 
t See Plate XXII, fig. 2. 

