402 E. A. BAUMGARTNER 
what more dorsal posterior extremity. These extend as furrows 
posteriorly from the lateral dorsal side of the caudal end of 
the middle part (fig. 25). As just stated, the posterior extremity 
is somewhat dorsal to the other parts of the anterior lobe and is 
directly ventral to the superior lobe. Two deep horizontal 
furrows constrict the connection between the posterior extremity 
and the superior lobe. 
The superior lobe is just below the saccus vasculosus to which 
it is closely attached, and is almost three times as wide as the 
posterior extremity of the anterior lobe (fig. 25). Its median 
part is about as long as the posterior extremity of the anterior 
lobe, but projects beyond it caudally and laterally. The caudal 
end extends somewhat dorsally. The lateral parts, or wings, of 
the superior lobe project somewhat upward and forward. 
The inferior sacs extend laterally from a constricted median 
connection. They are much smaller than the wings of the 
superior lobe, but, viewed from above, give the appearance of 
two lesser caudal wings. From their median connection a short 
slender canal extends in a slightly oblique direction upward and 
forward to connect with the anterior lobe (fig. 25). 
Fig. 2 Sagittal section of the hypophysis of an 8 mm. embryo. X 40 (H. 
E.C. 210). H, hypophysis; 7, infundibulum; Mo, epithelium of mouth; Mm, 
median mass connecting the premandibular somites; N, notochord; Po, post 
optic groove. 
Fig. 3 Sagittal section of the hypophysis of al5 mm. embryo. X 40 (H.E.C. 
228). For abbreviations, see figure 2. 
Vig. 4 Sagittal section of the hypophysis of al9 mm. embryo. X 40 (H.E.C. 
138). For abbreviations, see figure 2. 
Fig. 5 Sagittal section of the hypophysis of a 22mm. embryo. X 40 (H.E.C. 
231). AL, anterior lobe; Med, median connection of inferior lobes; SL, superior 
lobe; other abbreviations as in figure 2. 
Fig. 6 Sagittal section of the hypophysis of a28 mm.embryo. X 40 (H.E.C. 
234). St, hypophyseal stalk; other abbreviations as in figure 5. 
Fig. 7 Sagittal section of the hypophysis of a34mm.embryo. X 40 (H.E.C. 
362). For abbreviations see figure 6. 
Fig. 8 Sagittal section of the hypophysis of a 40 mm.embryo. X 40 (H.E.C 
370). P, parachordal plate; 7, trabeculae; other abbreviations as in figure 5. 
Fig. 9 Sagittal section of the hypophysis of a50 mm. embryo. XX 40 (H.E.C. 
444). (C, interhypophyseal canal; for other abbreviations, see figure 8. 
Fig. 10 Sagittal section of the hypophysis of a pup, (reconstructed from trans- 
verse sections). > 40. For abbreviations, see figure 8. 
