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first, the duodenum, descends straight down and thus turns slightly 
towards the right with its apex. The second loop lies on the right 
side, near the back, its distal third is bent upwards ; the whole 
loop is a closed one, and is retrograde with reference to the course 
of the duodenum. The third principal loop takes up the space 
between the first and the second loops, it is likewise retrograde, 
but open ; the middle portion of both its branches is irregularly 
kinked ; its ascending branch is accompanied by the two well 
developed cooca. The intestinal convolutions of Pedionomus are 
certainly different from those of either Turnices or Rasores. There 
is no indication of a horseshoe-shaped doubling of the second loop, 
nor do the convolutions of Pedionomus agree in numbers and 
other characters with those of the groups mentioned above. The 
convolutions of Pedionomus exhibit characters which are inter- 
mediate between those of Ralli, Turnices and Rasores, and which 
are at the same time peculiarly modified. 
Measurements : Absolute length of the intestine from the pylorus 
to the anus 47 cm. 
Relative length of the intestine 6*5 cm. 
Absolute length of the rectum 4*2 cm. 
Absolute length of one ccecum 5*5 and 7*0 cm. 
The liver of Pedionomus consists apparently of three almost 
equally sized lobes, owing to the left original lobe being split in 
half. In this respect Pedionomus agrees only with the Turnices 
and with the Rasores, it differs however from the latter and agrees 
with the former by the small size of the right lobe, which is 
scarcely half the size of the double left lobe. 
Skeleton. 
The number of cervical vertebra is fifteen in Pedionomus and 
in the Turnices, sixteen in the Rasores. The last two of these 
vertebra carry long dorsal ribs but without sternal portions. 
Although Pedionomus agrees with the Turnices in the number of 
cervical vertebra, it differs from the Turnices (at least from Hemi- 
podius pugnax , of Fuerbringer, op. cit. p. 240) in the composition 
of the brachial nerve plexus. The latter is formed in Hemipodius 
by the eleventh to foureeenth spinal nerves, in Pedionomus by the 
twelfth to fifteenth, in the Rasores by the thirteenth to sixteenth 
or thirteenth to seventeenth spinal nerves. In Pedionomus five, 
almost six ribs, belonging to the sixteenth to twentieth or twenty- 
first vertebra are attached to the sternum ; in the Turnices only 
three or seven, rarely five ; in the Rasores almost always four, 
very rarely only three. The greater number of these sternal ribs 
is a more primitive, Ralline character. The sternum of / edio- 
nomus is decidedly like that of the Turnices and differs in every 
essential point from that of the Rasores. The posterior max gin 
of the sternum possesses only one notch of moderate depth on 
each side, only the Processus lateralis posterior but no Proc. 
