. The Bashford Dean memorial volume : archaic fishes. Fishes; Sharks; Fishes, Fossil. Genital System of the Myxinoidea 87 into the body cavity, each suspended by a narrow strand of rnesovarium. The large eggs in this specimen are not very numerous; some were probably lost while the eel was being handled. In the next older female selected by Dean to illustrate the development of the ova (Figure 12), the eggs are from 11 to 13 mm. in length, but are much larger than the largest in the specimen shown in Figure 11; the increase in growth has been more in circumfer- ence than in length. The ends ar


. The Bashford Dean memorial volume : archaic fishes. Fishes; Sharks; Fishes, Fossil. Genital System of the Myxinoidea 87 into the body cavity, each suspended by a narrow strand of rnesovarium. The large eggs in this specimen are not very numerous; some were probably lost while the eel was being handled. In the next older female selected by Dean to illustrate the development of the ova (Figure 12), the eggs are from 11 to 13 mm. in length, but are much larger than the largest in the specimen shown in Figure 11; the increase in growth has been more in circumfer- ence than in length. The ends are not as pointed as they are in younger eggs. The in- creased weight of the eggs has stretched the mesovarium in the vicinity of each egg into a longer strand. A female with older eggs is shown in Figure 13, plate III. The largest of these eggs are from 15 to 18 mm. long, and they are likewise larger in the transverse diameter than those shown in Figure 12. A female with eggs that are almost ready to be deposited is shown in Figure 14, plate IV. The eggs are from 20 to 22 mm. long, and 7 to 8 mm. wide. The largest eggs recorded by Dean were 29 mm. long by 9 mm. wide. The aver- age length of seventy eggs was mm. The mesovarium in females containing eggs almost ripe is very broad, and is stretched into long, narrow, twisted strands at the places where the large eggs are attached. Sometimes adjacent strands of the mesovarium become â tangled together, and may even be tied in loose knots. A female containing large eggs usually has from 25 to 45 or more, and their contours can easily be seen from the exterior. The mass of the numerous mature eggs causes the body cavity to be slightly enlarged by expansion of its walls. Neither Dean nor I succeeded in catching any females with eggs lying in the body cavity, free from the ruptured ovarian capsules, ready to be deposited. European investigators likewise record that they have been unable to get any females of Myxme containing full


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