42 LIVERPOOL BIOLOGICAL SOCIETY. 
was supplied by the flexor sublimis, furnishing both the 
superficial and deep tendons to that finger. 
The abnormalities due to persistence of embryonic form 
depend upon defective development—that is to say, the 
part affected reaches a certain stage of development, but 
then, instead of advancing pari passu with the rest of the 
body, remains in a condition which, though normal to the 
embryo, is abnormal to the properly developed subject. 
In this class I include, not only the abnormalities con- 
sisting of the persistent embryonic form per se, but also 
those to which such persistence gives rise—as meningocele, 
spina bifida, ectopia cordis, and others. 
Everyone is familiar with the difference between sheep 
kidneys and what I believe, in domestic parlance, are 
usually called beef kidneys—the former have smooth, even 
surfaces, while the latter are composed of a number of 
partially united lobules. Well, all kidneys (above a certain 
class), in their early embryonic condition, are formed of- 
separate lobules, and it is only as development proceeds 
that these coalesce; and I have found an adult human 
kidney retaining this rudimentary form, the constituent 
lobules being very imperfectly united. 
In the embryo, the blood coming from the inferior vena 
cava is directed by the eustachian valve across the right 
auricle, and passes into the left auricle through an 
opening, the foramen ovale, in the inter-auricular septum. 
Usually this opening becomes occluded a few days after 
birth; but in specimen of which I obtained this session, 
this had not taken place, and the foramen remained large 
enough to admit the tip of the little finger. 
The two specimens exhibited, which are from our 
anatomical museum, show a persistence of two superior 
vene cave or precaval veins. ‘These two large veins are 
joined together superiorly by a transverse connecting 
