59 



The allantois has at tliis stage also, tlie band-hke appearance, and adlieres to the chorion. The lumen, however, 

 is so large, that when filled, it would probably have the appearance of a long cylindrical bag, which, attached to the umbilical 

 cord, extends out towards both ends of the chorion. 



The amnion, as in the smaller Phocæna fætus, was double, the fætus within being closely surrounded by the 

 epithelium stratum of the amnion, outside which was a space tilled with fluid, and limited peripherally by a stratum of 

 thin embryonal connective tissue. 



The umbilical cord showed a length of about 6 millim. and a diameter of 3V2 millim. The caudal side is 

 more convex and somewhat longer than the cephalic margin. No vesicula umbilicalis was visible exteriorly; it would probably 

 be found in a rudimentary condition on making serial sections through the umbilical cord. 



As regards the remarkable circumstance that the amnion is double, it would be worth a more careful in- 

 vestigation of more copious material; for from that at hand I could form no satisfactory explanation of the whole, on account 

 of its defectiveness. The recorded fact is, however, undoubted, as in both cases I found, on opening the outer amnion, 

 a perfectly transparent membrane within, enveloping the foetus very closely. 



No foetal membranes were attached to the third Phocæna embryo, as it came into my hands. 



