new Parasitic Copepods on Fish, 371 



thickened near the end, where the dentations are coarser ; the 

 point is more curved and minutely toothed. 



Length without processes 5 niillim., with processes 8 millim. 



The embryos when first hatched are rounded, with an 

 anterior projecting portion, and are sharp-pointed posteriorly, 

 on each side of which is seen a long bristle ; these bear on 

 either side three pair of limbs, the first ending in a single 

 hair, the second with three, the third pair with four. When 

 a little older the body is more distinctly segmented, the 

 second and third limbs become bipartite, each branch of the 

 second has a single joint terminating in two fine hairs ; each 

 branch of the third consists of two joints, the end one 

 giving off four long hairs. 



The male is seen to attach itself firmly to the abdomen of 

 the female by its powerful posterior antennas, the body 

 hanging freely between the long laminate processes. 



Note. 



The name " Helleria " being already appropriated for more 

 than one genus of crustacean animals, I propose to alter the 

 one so called by me (described in the Ann. & Mag. Nat. Hist, 

 ser. 7, vol. i., January 18U8, pp. 10-11, pi. v., and August 

 1898, vol. ii. pp. 93-94) to " Cyhicola^'' to avoid any con- 

 fusion. 



EXPLANATION OF THE PLATES. 

 Plate X. 



Fiy. 1. BomolocJms megaceros, (S , Heller, highly magnified. 



1 a. Anterior antenna. 1 b. Posterior antenna. 1 c. Second 



maxilliped. 1 d, e,f. First, second, and third peraeopoda. 

 1^. Fifth peraeopod. 1 h. Last abdominal joint and 

 caudal plates. 

 Fi(/. 2. Caligus longipedis, 5 , sp. n., from the back, enlarged. 



2 a. Cephalothorax from beneath, much magnitied. 2 b. First 



maxilliped. 2 c. Third perseopod. 2 d. Fourth peraeopod. 

 2 e. Caudal plates. 

 Fig. 3. Male of the same from the back, enlarged. 



3 a. Posterior antenna. 3 b. Hamulus, 3 c. Second maxilliped. 



Pjlate XL 



Fig. 1. Caligus robustus, 5> sp. n., from the back, enlarged. 



1 a. Ceplialothorax, much enlarged. 1 b. Outer branch of the 



second peraeopod. 1 c, d. Third and fourth perteopods. 

 1 e. Caudal plate. 

 Fig. 2. Male of the same from the back, enlarged. 



2 a. Posterior antenna. 2 b. Posterior extremity of genital 



segment. 



