SOME PARASITIC ACARI. 
401 
parasitic, living among the hairs, and they are furnished with the 
most remarkable apparatus for holding these hairs, to which the 
females of the present species cling so tenaciously that the grasp 
is often not relaxed even in death. The species now described is 
very much smaller than that previously known. 
The second species is a Symbiotes, one of the Sarcoptidse, and 
is a parasite of the hedgehog. I regret that I was not able to 
find the male of this species ; but I only had one hedgehog, the 
parasites were extremely few upon it, and these few were most 
difficult to catch, running up and down the quills of the hedge- 
hog and about between them with great rapidity. 
The third species, which is very minute, does not appear to fit 
satisfactorily into any known genus ; I have therefore been forced 
to institute a genus, “ G-oniomerus ,” for it ; the species will of 
course serve as a type for the genus ; it would be too soon to 
attempt to define the latter accurately in any other manner, 
particularly as the present species is so extremely minute as to 
render detailed observations of it most difficult. 
Myocoptes tenax, n. sp. (PI. XXVI. figs. 1-7.) 
Male. Female. 
mm. mm. 
Length about T5 '20 to '27 
Breadth about T1 TO 
Length of 1st and 2nd legs, without the 
claws, about ‘06 '06 
Length of claw of 2nd leg '08 '02 
Length of 3rd leg, without claw '04 '04 
Length of claw of 3rd leg '03 '02 
The colour and texture in both sexes is very similar to that of 
the only other known species of the genus, viz. M. musculinus, 
except as mentioned below. 
Male. — Diamond-shaped, the division between the cephalothorax 
and abdomen well marked by a nearly straight transverse line, 
the body being slightly constricted at this point. Outline of 
cephalothorax slightly and irregularly undulated ; that of the 
abdomen on each side convex anteriorly, then concave, and again 
convex posteriorly. The abdomen is not divided posteriorly into 
two pointed projections as in M. musculinus , but comes to a single 
central bluutish point. On each side of this point is a square 
projection, from each of the two outer corners of which springs a 
very long and powerful hair. Thus there are two pairs of these 
