Biology Reference
In-Depth Information
Figure 12.
Diagrammatic representation of the larval oesophagus (O), and anterior intestine
(I) during the metamorphosis of
P. marinus
. The larval oesophagus is separated into A and B
regions in the larva (a) to show the contributions of this structure to the changing alimentary
canal at stage 2 (b), stage 3 (c), stage 4 (d), and in the adult (e). The diagrams also show the
larval liver with intrahepatic gall bladder (GB), the extrahepatic common bile duct (EHCB),
and the location of the pancreatic islets (P). The cranial principal islet (CrP) appears and moves
towards the developing pericardial cavity (PC) with the forward movement of the larval
oesophagus, whereas the caudal principal islet (CaP) appears at the site where the EHCB
entered the larval oesophagus-intestinal junction. Note the disappearance of the gall bladder
and EHCB and the development of a diverticulum (D). (From Elliott, 1989).
