REVIEWS. 493 
front pair of legs ( p') have grown larger and stand out in front and on 
each side of the beak (R). The growing embryo again forces off the 
the o 
also by the deutovular membrane and the original egg-shell, the last two 
having lost a small portion of the anterior end. During the tritovum- 
Stage the fore pair of feet become curved in like claws, and the beak 
sinks down into the body. 
Now the six-footed larva (Fig. 8) breaks through the shell, and closely 
resembles the adult (Pl. 8, Fig. 9). The first pair of feet modified for 
grasping the hairs of the field mouse, on which it is a parasite, take the 
the mandibles (pr) assume a style-like form. After one or more moultings 
of t 
results, which the author considers as th e of a ne mily of 
Claparéde also suggests the affinity of Myobia to the Tardi- 
grades (Echiniscus and Lyd ella,) especially from the study of the struc- 
ture of the Style-like mandibles and their supports. We feel convinced, 
from the study of Claparéde's figures and descriptions, that this compar- 
ison is very significant, and this has led us to consider the Tardigrades 
às à family of mites, related to Myobia and Dem odex. 
like stage, the beak of the young closely resembling that of the tick. 
Also, in less complete form, that of a species of Tyroglyphus, in which he 
shows that the genus Hypopus ionis iri — eer yi is the 
beautifully drawn tad plates 
The author concludes with a short chapter entitled ** Für Darwin." He | 
j he organization of the mites, in rela- 
to the legs, by which they are enabled to grasp the hairs of their host, 
and instances the alternation in form and position of the first pair of legs 
in Myobia, and their wonderful adaptation for grasping the hairs of the 
mice on which they live. He also cites the case of as ecies 0 , 
in which, as described by Dujardin, there is, on the hinder edge of the 
“ge two scoop-like lips by which they cling to the hairs of their 

