442 E. A. BAUMGARTNER 
ing stalk is present (fig. 43). What apparently is the remains 
of the nuclear mass is surrounded by a narrow densely-staining 
cytoplasmic rim. The chromatin network has disappeared, 
but larger masses of densely staining chromatin are to be seen. 
The concentric arrangement of the connective tissue cells is 
apparent, but not so marked as in the younger stages. In another 
specimen, 40 mm. in length, a strand of connective tissue, extend- 
ing from a funnel-shaped mass of epithelial cells—continuous 
with the epithelial lining of the mouth—to the base of the hy- 
pophysis, indicates the position of the degenerated stalk (fig. 8). 
The hypophyseal attachment of the stalk is anterior to the groove 
connecting the inferior lobes. Soon after this time the cartilages 
at the base of the brain become continuous across the mid line. 
I wish to thank Dr. R. E. Scammon for his many helpful 
suggestions throughout this work. Thanks are also due to 
Dr. R. J. Terry for his kindly interest during its completion. 
SUMMARY 
1. The terms ‘anterior lobe,’ ‘inferior lobes’ and ‘superior 
lobe’ have been used for the several parts of the hypophysis of 
Acanthias. 
2. Rathke’s pouch forms the posterior part of the anterior 
lobe. The later evagination of the ectoderm, anterior to this, 
forms the middle portion and the anterior extremity of the an- 
terior lobe. 
3. The inferior lobes develop from the lateral sides of the pos- 
terior extremity of the anterior lobe, i.e., from the lateral sides 
of Rathke’s pouch. 
4. The superior lobe develops from the caudal (superior) 
end of the hypophyseal anlage. 
5. In the course of development the hypophysis shifts in posi- 
tion about 145 degrees, so that the upper wall becomes the floor 
and the ventral (anterior) surface the roof. 
