o8 REIGHARD—MAST. [VoL. XIX. 
in 
other hand, the very circumstantial account which v. Kupffer 
gives of the transformation of the tubular fundament of the 
hypophysis of the embryo of Acipenser into what is undoubt- 
edly the hypophysis of the larva, and his clear though very 
diagrammatic figures make it necessary to wait for a re-in- 
vestigation of Acipenser before pronouncing judgment. 
With our present knowledge it seems to us most likely 
that what v. Kupffer describes as the fundament of the 
hypophysis in Acipenser is really such. This view is strength- 
ened by the likeness of its development to that described for 
Amia. The dorsal diverticulum of the archenteron shown 
in v. Kupffer’s Fig. 13, between en. and vd., is the probable 
homologue of the Amia adhesive organ. V. Kupffer speaks 
of this structure as a “quer gelagerten Wulste des Entoderms, 
: der jederseits von der Mittellinie sich taschenartig 
gestaltet.”’ Its form is thus not unlike that of the Amia adhe- 
sive organ in an early stage, and its position is the same. V. 
Kupffer himself suggests its possible homology with the ante- 
rior head cavities of Acanthias, structures which in the pre- 
ceding paper are considered to be the homologues of the adhe- 
sive organ of Amia. 
If it be true that this diverticulum of the foregut of Acipenser 
seen in v. Kupffer’s Fig. 13 corresponds to the adhesive organ 
of Amia we should expect that the structure marked _ hf. 
(Haftscheibe) in the same figure is in reality a part of this 
entoblastic diverticulum and not, as stated by v. Kupffer, a 
thickening of the ectoblast. With this slight alteration v. 
Kupffer’s account of Acipenser would be in substantial agree- 
ment with that given for Amia in this and the preceding 
papers. 
LITERATURE CITED. 
DEAN, Basurorp, 1896. On the Larval Development of Amia calva. Zool. 
Jahrb., IX, 639-672. 
Goronowirscu, N., 1883. Das Gehirn und die Cranialnerven von Acipenser 
ruthenus. Morph. Jahrb., XIII, 427-574. 
Hatter, B., 1896. Untersuchungen itber die Hypophyse und die Infundi- 
bularorgane. Morph. Jahrb., XXV, 1, 31-114. 
