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568 Bashford Dean lAemorial Volume 



This description is of a live egg just taken from the body of the mother. I have found 

 a very similar condition in the encapsuled intra-uterine egg of the nurse shark, Ginglymo- 

 stoma cirratum (Text-figure 16). Here is a thick heavy capsule enclosing the huge round 

 yolk w^th its embryo surrounded by a clear glairy fluid — evidently the counterpart of 

 Nishikawa's "white'\ Lining the interior of the shell and particularly noticeable at the 

 ends is a thicker jelly-like material which cushions the yolk as the egg rolls about in 

 the saddle-bag-shaped uterus of the female Ginglymostoma as she twists and turns 

 in avoiding enemies. 



Nishakawa's drawing (Text-figure 4) shows an elHpsoidal egg in a capsule (natural 

 size) 135 mm. over the processes (following the curve of the long one). The egg proper is 

 100 mm. long by 65 deep, with an embryo 43 mm. long on it. Attention is called to the 

 blunt nipple-shaped process on the left, while on the right, the capsule terminates in 

 a finger-like curved process about 40 mm. long over its outer curve. The capsule is trans- 

 parent and here dravvTi to show the embryo and its circulatory system, but on the lower 

 side just inside the heavy line representing the capsule is a light line portraying the 

 raphe of the capsule. This extends from the end of the short blunt process along the shell 

 and out on the long curved process. This raphe is bilateral — the other half being found 

 on the side of the egg away from the observer. 



Dean's drawings of encapsuled eggs number eight, including the wind egg previously 

 referred to. These figures portray elhpsoidal eggs of two kinds: normal eggs with a blunt 

 nipple-shaped process at one end and a long curved finger-Hke process at the other; and 

 abnormal or at least unusually long eggs having at one end a long process with tendrils. 

 There are also four drawings of round eggs. The normal ellipsoidal eggs will be studied 

 first, the unusual types will later be considered in series. 



Dean has figured two elHpsoidal eggs of the normal type. The first is shown in both 

 dorsal and ventral aspects in Figures 7 and 8, plate I. Careful comparison of Figure 7, 

 plate I, with Text-figure 4, a reproduction of Nishikawa's Fig. 1. pi. IV, shows that 

 Dean"s figure is a copy of Nishikawa's. The embryo measures 43 mm. in both; the yolk 

 in Dean's figure is 65 x 100, in Nishikawa's the same. Likewise the eggs in ventral aspect 

 (Figure 8, plate I, and Nishikawa's Fig. 2, pi. IV) are identical. Nishikawa also had an 

 egg with a 50-mm. embryo on it, but he had no drawing made of it. This however, Dean 

 had drawn in both dorsal and ventral aspects as may be seen in Figures 9 and 10, plate I. 



Having cleared up these points, let us now return to a study of the ellipsoidal 

 capsules, which have been designated as normal. But first let it be said that no one else 

 has ever obtained or at any rate portrayed capsules such as these. Each of the capsules, 

 shown in Figures 7 and 9, plate I, has at the left end a rounded, blunt, nipple-shaped 

 process or eminence. On the right, each capsule terminates in a curved, finger-like 

 stumpy process, about 30 mm. long, and each curved m the same direction. In the drawing, 

 each egg has on its lower side a distinct raphe, whose relation to the blunt process is 

 obscure but which extends out onto the long curved process. The capsule of the younger 

 egg measures 128 mm. in a straight line, that of the older egg 143 mm. 



