48 Mr. A. Haly on Rhinodon typicus. 
shrinkage of a spawn-spent oyster in alcohol or chro mic-acid 
solution is excessive, and will, when complete, reduce the 
animal to one tenth of its bulk while alive. This shrinkage 
is due to abstraction of the water with which the loose spongy 
tissue of the exhausted animal is distended. A so-called “ fat” 
oyster, on the other hand, will suffer no such excessive dimi- 
nution in bulk when placed in alcohol or other hardening fluid. 
In consequence of this variable development of the reproduc- 
tive organs as well as that of the connective tissue of the 
body-mass, the amount of solid protoplasmic material con- 
tained in the same animal at different times under different 
conditions must vary between wide limits. And inasmuch 
as the nutritive and reproductive functions of animals are 
notoriously interdependent, it follows, in consequence of the 
enormous fertility of the oyster, that a vast amount of stored 
material in the shape of connective tissue must be annually 
converted into germs and annually replaced by nutritive pro- 
cesses. Plentitude or dearth of food are also to be considered; 
but it now becomes a little easier to understand the physiolo- 
gical interdependence of the reproductive function and the 
so-called fattening process. 
To a great extent what has been remarked in the preceding 
paragraphs of the wasting-away of the reproductive organs in 
Ostrea virginica seems to apply also to O. edulis and O. 
angulata. The last species has an extraordinarily thick body- 
mass, with the stratum of reproductive follicles of remarkable 
thickness, averaging a much greater development than I have 
ever seen in any other form. When the contents of this great 
mass of tubules has been discharged a diminution in the bulk 
of the body-mass must naturally ensue, probably accompanied 
by a wasting-away of the connective tissue and tubules, such 
as apparently occurs in the American species. From what I 
have seen of the generative tubules of QO. edulis in sections, 
they are evidently regenerated much as in O. virginica. In 
a few specimens: I find them almost entirely gone, or present 
only in an extremely rudimentary state. 
VI.— Occurrence of Rhinodon typicus, Smith, on the West 
Coast of Ceylon. By A. HAty. 
On January 5th a large female shark which I identify as 
Rhinodon typicus was entangled in the nets at a fishing- 
village called Moratuwa, twelve miles south of Colombo. The 
native population were greatly excited, and flocked in large 
