PERRIN ET AL.: GROWTH AND REPRODUCTION OF SPOTTED PORPOISE 



135° 130" 125" 120" 



0° 105° 100° 95" 90° 85° 60" 



76 



123 



12 



13 



63 



32 



Galopagos is c^ 



4 1 8 -■ 



32 



135° (30" 125" 120" 115° 110° 105° 100" 95° 90° 85° 80° 



Figure 2. — Samples of spotted por- 

 poise used in life history studies by 

 5° square. Does not include speci- 

 mens that were not at least 

 measured. 



Because the field program is a continuing one, 

 the sample sizes for the various analyses were 

 different and depended on how much material 

 was available at the time each analysis com- 

 menced. Restrictions on sample size are set out in 

 the text below. 



Laboratory Procedures 



Fetuses were measured with dial calipers or 

 with calipers mounted on a 1-m stick. Postnatal 

 animals were weighed to the nearest pound on 

 platform scales. Fetuses were weighed to the 

 nearest gram on a triple beam balance. Testes 

 were weighed to the nearest gram on a platform 

 balance. A 1-cm^ cube from the center of each 

 testis^ and a similarly sized sample of the 

 epididymis from midlength of the testis were sec- 

 tioned and stained with hematoxylin and eosin. 



*Some early samples were taken near the dorsal surface of 

 the testis. Tubule diameter in these was subsequently found 

 not to differ relative to length, weight, and age of the animal 

 from that in those taken at the center of the testis, and the lots 

 were therefore combined for analysis. 



The mounted sections were subsequently 

 examined under a compound microscope. 



Ovaries were weighed to the nearest 0.1 g on a 

 platform balance. They were then cut into trans- 

 verse sections approximately 1 mm thick with a 

 scalpel and the sections examined under a dissect- 

 ing microscope. The corpora albicantia in each 

 ovary were scored to eight categories based on 

 size, color, vascularization, and gross appearance 

 (categories described below). If a corpus luteum 

 was present, it was measured with dial calipers to 

 the nearest millimeter in its three largest dimen- 

 sions. The diameter of the largest follicle was 

 measured to the nearest 0.1 mm. 



Age was estimated for 442 animals by exami- 

 nation of dentinal layers in the teeth. Three or 

 four teeth were extracted from the lower right 

 tooth row at approximately midlength and 

 mounted on wooden blocks in dental wax or plas- 

 tic resin. A longitudinal section 0.012 inch 

 (0.31 mm) thick was cut from each tooth with a 

 diamond saw. The sections were cleared for sev- 

 eral days in a 1:1 mixture of glycerine and 95% 

 ethanol, mounted under cover slips in balsam, 

 and examined with transmitted light under a 



233 



