J. F. McCLENDON. 



genital segment, where they are much convoluted and increase 

 greatly in diameter and each communicates by an opening, the 



os uteri, with an egg string that trails 

 behind the animal. The ovary is formed 

 of a much convoluted cord of cells in a 

 single linear series, small at the oogonial 

 end and gradually increasing in diameter 

 until it passes into the oviduct. As these 

 cells (oocytes) grow in the ovary they 

 become much compressed in the direc- 

 tion of the long axis of the cord and the 

 cell boundaries almost completely dis- 

 appear. Passing into the oviduct, the 

 oocytes continue to grow and soon their 

 boundaries reappear, and they become 

 more flattened as they grow larger. 

 There are at least two broods in the ovi- 

 duct at once, caused by the periodic 

 activity of the ovary. The younger 

 brood extends some distance into the 

 genital segment and is sharply marked 

 off from the older brood, which occupies 

 the last coils of the oviduct and consists 

 of oocytes that have nearly or quite 

 completed their growth. As the oocytes 

 pass out through the os uteri they are 

 fertilized from the seminal receptacles 

 (Fig. 2, sr") and surrounded with secre- 

 tion from the cement gland (f-g.~) which 

 forms the wall of the egg string. The 

 eggs are distorted when passing through 

 the thorax, but in most cases regain their 

 symmetrical form. Embryos in the egg 

 strings have their heads turned latero- 

 ventrally and their ventral surfaces ante- 

 riorly, in relation to the mother. Occa- 

 sionally one finds an embryo reversed, 



e.cx 



FIG. I. Female reproduc- 

 tive organs of Caligus bonito. 

 ( Drawn by Emerton from Wil- 

 son's CaligidiT.} c. g., ce- 

 ment gland ; e. c. , external 

 egg cases ; o , ovary ; o. d. , 

 oviduct; s. r., semen recep- 

 tacle. 



or partially rotated. 



