A NEW CUTANEOUS PARASITE, THE ENTOZOON FOLLICULORUM. 
317 
arguments for regarding it as an Annelidan. While, on the other hand, Mr. Gray 
of the British Museum, to whom I submitted the animal, considers it to be allied to 
the Entomostracous Crustacea, to that group of animals intermediate between worms 
and insects, of which De Blainville speaks in the following terms : — “ Genre d’ani- 
maux tellement bizarres au premier aspect, que les zoologistes sont encore fort peu 
d’accord sur la place qu’ils doivent assigner a ce groupe dans la serie animale”*. 
Note . — The foregoing paper was first communicated to the Royal Society in De- 
cember 1842 and was read in March 1843 ; previously to being again communicated 
it was remodelled, the facts remaining the same. — E. W. 
Explanation of the Plates. 
PLATE XV. 
The whole of the figures, with a few exceptions stated in the references, are drawn 
to a scale of one line to the -^roo of an inch. 
Fig. 1. A dorsal view of the long variety; showing tegumentary and internal texture. 
This animal measured ^ 3 - of an inch in length. 
Fig. 2. A side view of the same. 
Fig. 3 . A ventral view of the same animal ; the mouth is well shown. 
Fig. 4 . The short variety ; a dorsal view, the head retracted, and seen through the 
transparent integument of the thorax. The specimen measured of 
an inch in length. 
Fig. 5. The same animal ; seen upon its ventral surface. 
It will be remarked that these figures are not extremes of measurement ; but the 
difference between them is nevertheless very striking. In addition to relative length 
of abdomen, the caudal extremity forms a conspicuous character. 
Fig. 6. A group of animals found in the sebaceous substance of a living person. This 
and the two following figures are not drawn to a scale. 
Fig. 7- A similar group, situated within a hair-follicle. 
Fig. 8. This figure represents a hair-follicle, with two sebaceous glands opening into 
it. An Entozoon folliculorum is seen between the cylinder of the hair and 
the follicle. It must be remembered that the hair is one of the minute 
downy hairs of the skin. 
Fig. 9. The head, viewed upon its under surface. 
a. One of the cephalic palpi, curved downwards; its prismoid truncated 
extremity is seen, as also the phalanges. 
b. A spine or tubercle on its penultimate segment. 
c. The reniform body. d. The antennae- like palpi. 
e. The four labral palpi. 
* Dictionnaire des Sciences Naturelles. Article Lernee. 
