284 A New Acarite. By M. A. L. Donnadieu, D.Se. 
all my search for others, was but that of a single individual, I 
believe that it is an undeveloped form (hypopiale) of Gamasus, 
which might very well have proceeded from one of the Diptera 
which I shall refer to. ‘The mouth, too badly defined to have any 
significant value, the general form of the body, and, above all, the 
absence of reproductive organs, seem to me to confirm this idea. 
I would observe that my description refers to the actual form of 
the individual, without in the slightest degree indicating what the 
ultimate appearances may be. I have called it Heterotrichus 
inequarmatus, which name can be applied to the complete form 
when I am fortunate enough to obtain it. 
The body, which is very transparent, is ovate; the rostrum 
makes a very slight bend forwards, through which one distinguishes 
only that which should be the palpx. The inferior surface is, 
flattened, the upper one is swelled out (bombée). ‘The skin on the 
entire region of the body is granular, and presents grooves in 
the neighbourhood of the feet and rostrum. 
On the dorsal face one sees a series of rounded elevations like 
little tubercles. At their level the skin is slightly brownish ; they 
serve to support the hairs which by their nature justify the generic 
name that I have given the animal. 
These hairs are, in fact, of two kinds. The one spiny at their 
ends seem formed of a series of joints, which fit one into the 
other. They are twice to three times the length of the body. 
They are comparatively slender, but are nevertheless rigid enough 
to give the animal the appearance of a body covered with sharp 
spines. ‘The others are short, and terminate in a slender point; 
almost in the middle they present a very large vesicular swelling 
filled with a mucous-like fimd, which by its transparence contrasts 
vividly with the brownish tint which fills the rest of the hair. 
The disposition and number of each of these hair-like processes 
on their little elevations of the surface are unimportant; but these 
latter are so abundant that the whole body disappears beneath the 
mass of hairs which cover it. 
The feet, eight in number, are short and decidedly conoid. 
They differ very slightly in length, the anterior pair being slightly 
shorter than the others. ‘Two pairs are directed in front, and two 
Betas At the point of origin they sensibly approach each 
other. 
Their mode of termination is the most remarkable point about 
them. The conical tarsus is terminated by a wide membrane 
capable of forming a cupuliform caruncula, on the lower border of 
which are placed hooklets. The latter are of two forms, and their 
appearance led me to give the specific qualification to the animal of 
imequarmatus. The first are freely bent, as is the case in the 
majority of the species. They thin away from base to extremity, 
