A NEW CUTANEOUS PARASITE, THE ENTOZOON FOLLICULORUM. 
307 
to be formed by a bifurcation of the head and by the prolongation forwards of the 
divided portions, to an extent which is about equal to one third of the length of the 
head. In structure, the cephalic palpi are composed of three or four annulate seg- 
ments connected by capsular membranes, the last segment or carpus having its flat 
and triangular palm furnished with four or five membranous claw-like phalanges with 
obtusely pointed extremities. On the outer angle of the penultimate segment is a pro- 
minent tubercle, which has the direction of the axis of the arm. The cephalic palpi 
are furnished in their interior with muscular fibres, which form a thin stratum beneath 
the integument, and are continuous posteriorly with the general muscular system of 
the animal. Of this muscular apparatus, the flexor and extensor fibres are most 
strongly marked. 
The motions of the cephalic palpi are extensive and powerful in the direction of 
flexion and extension, but very limited in the sense of abduction. By virtue of the 
laxity of the capsular membranes of their annulate segments, they also admit of re- 
traction. The actions of flexion and extension aid the animal in progression, and 
in consequence of the inward obliquity of their movement, they also serve the office 
of organs of prehension, by conveying directly to their mouth portions of sebaceous 
substance, from which the animal may suck the juices. 
The upper surface of the head is depressed, sloping gradually downwards and for- 
wards from the occiput to the extremity of the snout, which is either curved suddenly 
downwards or slightly upwards, according as the animal is seen in the state of flexion 
or extension of its cephalic palpi. Along the middle of the head in its longitudinal 
axis is a slight groove caused by the prominence on each side of the cephalic palpi ; 
and lodged in this groove is a flask-shaped flattened organ (labrum ?) which forms a 
part of the base of the head behind, and terminates anteriorly opposite the bifurcation 
of the cephalic palpi in a linguifonn point. The flask-shaped organ is slightly curved 
in its form ; its upper surface being smooth and convex, the under concave. From 
the concave under surface there appear to proceed four pairs of jointed tentacula, 
which in the first instance pass forwards, and becoming perceptible beyond the end 
of the flask-shaped organ, give rise to the appearance of a succession of progressively 
diminishing rounded segments, and then bend downwards to either side of the mouth 
of the animal. Proceeding also from this organ as far back as the base of the neck 
of the flask are two larger, antennse-like tentacula, which seern to arise from its 
under part at each side and run forwards parallel with the neck of the flask and its 
segmented prolongation. Immediately in front of the latter, the larger pair of ten- 
tacula approximate and pass onwards parallel with each other to near the extremity 
of the snout, where they curve downwards and backwards to the front of the mouth. 
These tentacula are slightly constricted from point to point, the constrictions probably 
performing the office of joints, and at their termination are slightly curved outwards. 
They are capable of a moderate degree of movement in the direction of flexion and 
extension. 
