FISHERY BULLETIN: VOL. 81. NO. 2 



colored gelatinous material probably contains 

 ovalbumin and mucus, in different proportions. 

 The dimensions are usually similar to those of the 

 Type II capsules but may vary, as total lengths of 

 up to 1 70 mm were observed in capsules with very 

 long tails (Fig. 5B). These capsules were most 

 common during the first 3 mo of gestation. 



Type V "short tail" gel capsules (Figs. 4B, 5A) — are 

 the smallest capsules, are generally flattened, and 

 contain only gelatinous ovalbumin/mucoid ma- 

 terial. These capsules were also most common 

 during the first 3 mo of gestation. 



Type VI embryo capsules — contain an embryo and a 

 reduced volume of yolk. Despite the presence of 

 multiple ova and several blastodiscs in embryo 

 capsules, dissection of all Type VI capsules failed 

 to show more than one embryo developing within 

 a single capsule. 



Prior to entering the uterus, egg capsules of the 

 same type were found in similar positions in both 

 oviducts of a particular adult. No matter how many 

 eggs were ovulated, encapsulation of albumin would 

 occur synchronously in each oviducal gland, thus pro- 

 ducing egg capsules of the same type at the same 



time. Calculation of egg capsule production rates, 

 based on changes in uterine capsule numbers, in- 

 dicates that capsule formation takes place at 24-36 h 

 intervals. Initial egg capsules contain ovalbumin and/ 

 or mucus derived from the oviducal gland. As the 

 ovulation rate and the number and volume of ova in- 

 creased during later stages of gestation, more ova 

 were present in the oviducal gland when encapsula- 

 tion occurred. At this time only ovoid yolk capsules, 

 Type II, were found in the oviduct and uterus. 



Embryonic Development 



Multiple embryos from 0. taurus develop in each 

 uterus during the early stages of gestation. However, 

 the maximum number of capsules containing mac- 

 roscopic embryos is low (no more than 9% or 2-7 of all 

 capsules in both uteri combined at any given time). 

 Encapsulated embryos were found from June to Sep- 

 tember. The maximum number of embryos in a single 

 uterus was seven, ranging in size from 19 to 334 mm 

 TL. Four of these seven were found in the mouth and 

 stomach of the largest embryo. After June, the num- 

 ber of undamaged encapsulated embryos and the 

 percentage of capsules with blastodiscs declined. 



B 



1mm 



Figure 6. 



-Three views of a 13 mm embryo (IRCZM 103179) taken from an adult Odontaspis taurus, 27 4. 2 cm long, captured 8 July 1978. 



Left side; (B) dorsal; (C) ventral. 



(A) 



210 



