138 FORMATION OF SHELLS OF ANIMALS, ETC., 
were in a very early stage of development, as can be seen 
by their size, which in the plates in the ‘ Philosophical 
Transactions’ is given, and the figures represent entire 
animalcules; also, by the diminutive size of the part 
containing the calcareous particles, called the neck, which is 
an infallible proof of their immaturity, being, in these 
specimens, scarcely at all developed ; and by there being, 
in two of them, only a few of the hooklets, the regular 
number in the perfect animalcule being twenty-six; and 
in the second place, I may observe, that the hooklets, 
which are represented in the plates, were not detached, but 
are drawn as they were seen in their natural situation in 
the unmutilated animalcules. And having besides the 
specimens by me from which the drawings were taken, I 
am enabled to give satisfactory proof that neither the 
descriptions nor the plates are made up partly from facts, 
and partly from imagination. I may also notice, that it 
would not have occurred to me that these changes could, 
by any one, ever have been attributed to a state of degene- 
ration occurring, as they do, in eysticerei which had not yet 
got the full number of these organs, had it not been stated 
that such was the explanation given by some pathologists. 
The next part, showing the fact of molecular coales- 
cence, which I shall describe, will be the crystalline lens ; 
and, in examining its true structure and mode of forma- 
tion, I shall follow the same rule as that observed in the 
other tissues, namely, that of selecting such specimens as 
will afford the best opportunity of seeing, in as natural a 
state as possible, the earliest stage of its development, and 
the changes of structure dependent thereon, without the 
necessity of employing such chemical substances, or 
mechanical mutilation as cannot fail to render the ap- 
pearances presenting themselves during the examination 
