320 CHIKANOSUKE OGAWA 
Because the alveolar ducts often ramify successively and the 
walls are irregularly shaped, it is difficult to ascertain the type 
of ramification. But after careful examination I recognize the 
presence of both dichotomy and monopody types predominating 
Figs. 4 and 5. Diagrams of projection of the alveolar ducts in the positive 
model. Magnification same as above figures. Thin lines denoting air-sacs. 
Dotted lines denoting covered parts. 
in alveolar ducts. ‘The accompanying diagram (fig. 6) shows 
the type of ramification in my model. Dotted lines represent 
the parts where the reconstruction is not complete. In my 
diagram the angle and length of the branches are not considered 
with care. 
