240 



THE ANATOMY OF INVERTEBRATED ANIMALS. 



her body near the vulva. On close examination, however, he 

 is seen to be firmly fixed by his antennary hooks to one of the 

 two triangular lobes described above. The hooks are doubt- 

 less at first attached to the lobe by muscular contraction ; but 

 the connection once effected seems indissoluble — at least ma- 

 ceration in caustic soda does not cause the male to become 

 detached. It does not appear that more than one male is 

 attached to a female. 



The body of the male (Fig. 62) is pyriform, and exhibits 

 indications of a division into six segments beside the head. 



Fig. 62.— -<7, Male Chondr acanthus, in situ, enlarged : x, vulvae of female ; w, trian- 

 gular papillose lobes ; q, antennae of male ; r, eye-spot ; t, testis ; u, vas deferens ; 

 v, genital aperture ; y, rudimentary appendages of the female ; g, ovisacs. 



The anterior extremity presents a black eye-spot imbedded 

 in its substance, and gives origin to a pair of rudimentary 

 antennules, and to the strong, booked, prehensile antennae. 

 Behind and below them is a large labrum and three pairs of 

 hook-like gnathites. These are succeeded by two pairs of 

 subcylindrical appendages, which apparently represent ambu- 

 latory limbs. 



The caudal extremity is terminated by two styles, and 

 there are two prominent tubercles on the ventral surface of 

 the penultimate somite, in which the genital apertures are 

 seated. The alimentary canal is a delicate, irregular tube, 

 having many brownish granules imbedded in its walls. A 

 wide oesophagus is connected with its anterior extremity ; 

 but the opposite end appears to be rounded, and to be united 

 with the ventral surface of the integument only by connec- 

 tive tissue. A complex muscular system, composed of striped 

 fibres, is visible through the integument, and the eye-spot 



