ANATOMY AND METAMORPHOSIS OF CYCLOPS. 231 



convey the seminal fluid from the testes to the second 

 chamber, is usually empty, since the seminal fluid passes 

 through it quite rapidly to the second portions. 



(ii.) The second region or spermatoph ore-forming por- 

 tion (vd. 2} is not abruptly separated from the first division. 

 It reaches from the carapace to the first abdominal somite, 

 and its cavity is usually distended by the spermatozoa 

 which have passed to it from the testes through the first 

 division. They are here stored up, and, as they accumu- 

 late, are packed together to form a complex spermatophore y 

 which will be more fully described later. 



FIG. 123. 



FIG. 123. Outline of the right side of the body of a male speci- 

 men of Cyclops tenuicornis, without the appendages, to show the repro- 

 ductive organs. (From Graber, Beitraye zur Kenntniss der Generations- 

 orr/ane der freilebenden Copepoden. Zeit. f. Wiss. Zool. xxxiii. Taf. 

 xxv., Fig. 1.) 



L Testis. vd, t. The first or proximal region of the vas deferens. 

 vd. 2. The second or spermatophore-fonning region, vd. 3. The third 

 region, or receptacle of the spermatophore. 



(iii.) The third region (Fig. 123, vd. 3) is a short, en- 

 larged pouch, the receptacle of the spermatophore, sepa- 

 rated by an abrupt constriction from the second region, 

 and opening externally on the posterior edge of the first 

 abdominal somite, under a small lid or flap (Fig. 124, h) 

 which carries three stout hairs projecting backwards from 

 its free edge. After a spermatophore has been formed in 



