390 LEFEVRE. [VoL. XIV. 
of the ampullae. I have failed to find any cilia on the latter, 
as Chandelon (2) has described in Perophora. Pl. XXXII, 
Fig. 31, shows a cross-section of the intestine (zz¢.), surrounded 
by the thin-walled tubules and ampullae (am.), the flat cells of 
which contain very deeply stained nuclei. On one side of the 
figure one of the ducts is cut longitudinally, just where it forks 
near the surface of the intestine (0.7d.). 
Different views have been held concerning the function of 
the “organe réfringent.” Krohn (15), Kuppfer (16), and Giard 
(6) have regarded: it as a renal organ; but as the ampullae 
always contain a clear, unstainable fluid, and never concretions 
or epithelial débris, this view has been discarded. A second 
hypothesis, that it is a digestive gland which gives its secretion 
to the intestine, has been held by Chandelon (2) and Della 
Valle (3), the latter attributing to the organ an hepato-pancre- 
atic function. Pizon (22), however, believes that the flat cells 
of the ampullae possess no glandular characters, and cannot be 
reconciled with a secretory function; but he is inclined to 
regard the organ as a chyliferous apparatus. He says (loc. cit., 
p. 96): “Je suis plutét porté a croire que |’épithélium des 
ampoules ne sécréte rien, et qu il se charge simplement 
d’absorber les produits de la digestion qui sont assimilables et 
qui n’ont pas été pris par les parois de l’intestin. Ces produits 
quitteraient ensuite la cellule pour aller se mélanger au sang, 
dont les corpuscules sont précisément extrémement nombreux 
autour des ampoules terminales.’’ Although Pizon’s hypothe- 
sis would seem the most probable one, as the histological struc- 
ture of the organ is not such as to suggest a glandular function, 
still, the réle played by the “‘organe réfringent ’’ must remain 
uncertain until the nature of the liquid contained in the tubules 
is determined. 
The Pericardium and Heart. 
Concerning the origin of the common rudiment of the peri- 
cardium and heart, investigators have given widely divergent 
accounts, some deriving it from endoderm, others from meso- 
derm. Although it is very certain that this structure arises 
