. Bulletin of the United States Fish Commission. Fisheries -- United States; Fish-culture -- United States. 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 togeth
. Bulletin of the United States Fish Commission. Fisheries -- United States; Fish-culture -- United States. 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 Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States Fish Commission. Washington, The Commission, Govt. Print. Off
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