UROGENITAL SYSTEM OF MYXINOIDS 



123 



mm. of mesovariun in young females, and even less in adults. 

 The following table shows the number of larger eggs present in a 

 few individuals : 



None of the eggs are so far advanced as to have hooks at the 

 ends. 



In shape, the eggs are round until they reach a diameter of 

 about 1.5 mm., then they begin to elongate, and become oval. 

 Eggs 2 mm. long a e 1 to 1.5 mm. wide. The eggs are developed 

 between the two layers of peritoneum which form the meso- 

 varium, as shown in figure 74. When the eggs begin to assume 

 the oval shape, the pointed ends project beyond the place of 

 attachment to the mesovarium, and one end evidently grows more 

 rapidly than the other for the largest eggs are usually attached 

 between one end and the equator, leaving the ends free (fig. 67). 



Other structures besides eggs may be present in the mes- 

 ovarium. Specimen no. 20 has 33 empty egg envelopes, the 

 'corpora lutea' (fig. 68). The largest eggs in this animal are 

 approximately 1 by 1.5 mm. Specimen no. 2 has, besides the 

 27 large eggs, two corpora lutea, each of which is the same size 

 as the envelopes around the eggs (8.5 by 20 mm.), and which 

 has been opened along one side (fig. 69). The corpora lutea in 

 Myxine no. 20 are much smaller (4 by 6 mm.) and' are shrunken 

 into a compact mass. Myxine no. 5 has 25 or 30 of these corpora 

 lutea which are still smaller (2 by 3 mm.) than those of speci- 

 men no. 20, as shown in figure 70. The largest eggs of specimen 

 no. 5 are 1.5 to 2 by 0.5 to 1 mm. Specimen no. 1 has several even 



