238 THE ANATOMY OF INVERTEBRATED ANIMALS. 



an illustration of the most remarkable peculiarities of this 

 aberrant group. 



The female (Fig. 61) is not more than half an inch long, 

 but, posteriorly, two long slender cylindrical filaments (like 

 the rest of the animal, of a whitish or yellowish color) are 

 attached to its body, which is broad and flattened, and as it 

 were crimped at its edges, so as to present two principal 

 transverse folds. The angles of the folds are elongated into 

 lateral processes (/i, /,/"), and similar processes (c?, e) proceed 

 from the middle line of the body, which by these outgrowths 

 and foldings becomes singularly distorted ; and the grotesque- 

 ness of the animal's appearance is not a little enhanced by 

 the bowing motion, accompanied by a flapping backward and 

 forward of its gouty limbs, which it executes when detached 

 from the integument of the Lophius. 



The head is expanded into a sort of hood, the convex 

 anterior margin of which bears the antennules and antennae, 

 the latter being metamorphosed into the strong curved hooks 

 by which the Cho)idr acanthus is securely anchored to the 

 infested animal. A subquadrate labrum overhangs the mouth, 

 but does not inclose the mandibles and form a suctorial ap- 

 paratus, as it does in some Ep'izoa. 



The mandibles and the two pairs of maxilla resemble 

 curved hooks or claws. Two pairs of appendages (Fig. 61, 

 5, c), composed each of a protopodite, terminated by an endo- 

 podite and exopodite and exhibiting hardly any trace of 

 articulation, are attached to the anterior part of the body 

 behind the head. 



The body ends in a rounded segment, situated in the deep 

 notch between the hindermost marginal processes, and bear- 

 ing the two projecting vulvae. Above each of these is a small 

 triangular papillose lobe (Fig. 62, w)^ probably a modified ap- 

 pendage, to which, as we shall see, the male attaches himself, 

 while below them are two other rudimentary appendages 

 (Fig. 62, y). The alimentary canal is a straight tube running 

 from the mouth to the opposite extremity of the body. No 

 heart is discoverable, and the nervous system and organs of 

 sense (if any) are equally undistinguishable. The interspace 

 between the alimentary canal and the walls of the body is 

 almost wholly occupied by the ovarium, which consists of 

 four tubes, situated on each side of the intestine, and giving 

 off" ramified caeca, in w^hich the ova are developed. Ante- 

 riorly, each pair of tubes opens into the oviduct of its side, 

 which passes do\vn along the side of the body to terminate at 



