REVIEWS. 
5 77 
dental groove remains behind as the lining to the socket of the tooth, while 
the portion which was reflected over the primitive dental papilla again comes 
to the surface as a covering of enamel — the two having now between them 
a third substance, the crusta, and which has been formed by the changes that 
each in part has undergone. These views of the development of the dental 
tissues will be made the more apparent if the series of objects in the diagram 
are attentively examined.” 
It must be evident, from what we have seen, that the 
present is a work of original character, and rare value in 
veterinary literature. It professes no archetype save nature’s 
impress ; follows no guide save that which has preceded it 
in the same field of research. The illustrating engravings, 
showing forth the structure of the teeth, their formation, and 
the changes they undergo in the ox, sheep, and pig, ad- 
mirably and strikingly pourtray the several phases of change 
of the teeth in the various processes of formation and growth, 
and add great value to the work. Professor Simonds’ name 
will be long associated with a subject which, hitherto, had 
long lain dormant, or was so imperfectly or inaccurately 
knowm to agriculturists, that their knowledge w T as too fallible 
to be depended upon, and too superficial to be really and sub- 
stantially useful. In short, there v 7 as a great void in this de- 
partment of the agriculturists’ labours, and this void Professor 
Simonds has filled so completely as to leave little room for 
future inquirers in the same field of research, unless it be to 
those who plough deep, and look narrowly into the veins of 
science. 
XXVII. 
75 
