332 Dr Duckworth , A critical description of three cases 
the cloaca being but partially subdivided, and although recog- 
nisable by their position, the portions referable to bladder, uterus, 
and rectum are conjoined. From the lower surface of the im- 
perforate cloaca, an urethral process passes directly backwards 
to end eventually as the sessile clitoris already seen in the gluteal 
region. 
The sex is clearly shewn by the pelvic organs, for an ovary is 
present on each side, together with the corresponding Fallopian 
tube. Suprarenal bodies are present, and very large. The right 
kidney is represented by a large multilocular cyst, which touches 
the left kidney. The latter is unusually small, tough, and elastic. 
From each kidney, the ureter passes down to the conjoined cloacal 
structures : the right ureter is dilated at its lower end, while the 
left is unchanged in diameter. 
The most striking feature of the abdominal arterial system is 
a large median vessel which at first sight appears to be the 
continuation of the dorsal abdominal aorta below the coeliac 
axis and superior mesenteric artery. This median artery arches 
forwards over the uterine part of the cloaca, deeply grooving it, 
and passes downwards in the middle line over the rudiment of 
the bladder. Immediately above the symphysis pubis it gives off 
symmetrical branches to each side of the pelvis, and thereafter 
bends upwards to enter the umbilical cord as the single umbilical 
artery (cf. Fig. 12). 
That the dorsal abdominal aorta should assume such an unusual 
course and pass down on the ventral aspect of the viscera seemed 
so unlikely that a minute examination of the aorta was under- 
taken. As a result, the ventral vessel was found to be the larger 
of two branches into which the dorsal aorta divides. The smaller 
branch retains the dorsal position, and continues caudally upon 
the vertebral column to end in an arteria sacra media, after giving 
off distinct branches to the right and left sides of the pelvis. 
In other words, the dorsal abdominal aorta instead of dividing 
at the level of the 4th lumbar vertebra into right and left 
common iliac branches, bifurcates at a much higher level, and 
gives off not lateral vessels, but a larger ventral branch and a 
smaller dorsal vessel. The latter provides small symmetrical 
pelvic branches identified provisionally with the proximal portions 
of the common iliac arteries. This condition resembles, in im- 
portant particulars, that described above in specimen E. 
It remains therefore to attempt to provide an explanation of 
the morphological value and status of the great ventral offshoot. 
This, as already remarked, terminates partly as the single 
umbilical artery, but not without giving off symmetrical right 
and left branches which pass around the true pelvic brim from the 
front of the bladder. 
