BULLETIN OF THE UNITED STATES FISH COMMISSION. 195 



a very small area of insertion on the outer surface of the egg-membrane. 

 There are four of these filaments/, as indicated in Figs. 1, 3, and 4, and 

 when the eggs are first emitted they are coiled around the egg-mem- 

 brane externally in a spiral manner, as shown in Fig. 1. Very soon 



after oviposition they commence to uncoil from around the egg, and 

 when a number are stirred or shaken about in a small dish they soon 

 become entangled together so as to hang together in bunches or strings. 

 These threads are about eight times the length of the diameter of the 

 ovum, and are apparently composed of the same tough material as that 

 which enters into the formation of the egg-membrane itself. In the im- 

 mature condition, and when the ovarian egg is still far from full-grown, 

 I find the threads present on the outside of the zona or membrane, but 

 closely adherent to the latter, as may be seen in Fig. 2, representing 

 a young and immature ovarian egg. In this condition the membrane is 

 relatively thicker than in more mature eggs, and the nucleus n is quite 

 conspicuous at the ceuter of the immature vitellus. 



The filaments/, Fig. 4, at the point of attachment to the egg-mem- 

 brane are somewhat enlarged, but have no bulbous base as in the case 

 of those found on the ova of the silver-gar. The egg is heavier than 

 sea- water, the oil-drops o embedded in the yelk y seeming to have no 

 tendency to buoy them up. 



