BENIRSCHKE ET AL.: OVULATION IN DOLPHINS 



MEASUREMENT IN CM 

 SECTION 



Figure l. — Diagram of dolphin uterus. Arrows indicate mea- 

 surements taken in Stenella spp. and squares denote location of 

 histologic sections. 



corpora lutea nor corpora albicantia. Because of 

 their size it was assumed that they were at the 

 verge of maturity. As shown in Figure 2, uterine 

 horns were of equal size, there were no stretch 

 marks and the endometrium was flat. Numerous 

 Graafian foHicles of varying stages of development 

 were present in both ovaries, but there was no 

 evidence of ovulation. The endometrium was thin 

 and composed of tubular glands possessing neither 

 secretion nor mitoses; the stroma was devoid of 

 inflammation and edema or hyalinization (Figure 

 3). The fallopian tubes were small and empty. In 

 all subsequent specimens, slides of fallopian tubes 

 were examined. No relevant changes were ob- 

 served and they are therefore not described 

 further. Also, sections of the lower uterine seg- 

 ment were found to make no contribution in the 

 assessment of reproductive state and are not in- 

 cluded in this analysis. 



Group II, Mature Females 



These six S. longirostris measured from 173 to 

 186 cm in length and were adjudged to be mature 



Figure 2.— Immature uterus oi Stenella longirostris (no. 1, Table 2). Note the flat folds of endometrium, equal-sized horns, and lack of 



serosal stretch marks (center) 



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