OECELLA. 371 



mother. A second female caught on the 16th July, and which proved to be a virgin, 

 was rather emaciated ; the neck being well defined and the angles of the ribs dis- 

 tinctly indicated. The under surface half-way between the pectoral flippers and 

 the genital slit was marked by a deep longitudinal mesial furrow fully an inch in 

 depth, and from the anterior extremity of this a branched depression was prolonged 

 forwards widening into a rounded hollow over the sternum. The genital slit was 

 42"- 80 from the tip of the snout, and 4"' 20 in length, and the anus was l"-50 

 removed from its hinder end. The left mammary slit was the longer, measuring 

 0"-38 in length, and that of the right side was 0"'33 long, the distance between 

 them posteriorly being l"-33 and anteriorly l"-46. The anterior end of the left 

 slit was 2"-06 from the anterior end of the vulva. The right ear in this speci- 

 men was 0"-08 in diameter, but on the left side it was so reduced that I did not 

 detect it for some time, and it would hardly admit the passage of a fine bristle. The 

 moustachial bristles had been shed, but their position was indicated by the pits in 

 which they had stood. 



This example yielded the following girth measurements : — 



Inches. 



Circumference one inch behind the blow-hole 27*75 



„ of the neck 27'25 



„ behind the pectoral flipper 31-00 



J, in front of the dorsal fin 29*75 



„ anterior third 2475 



„ behind the anus 20*00 



„ at the root of the tail . . 9-20 



Distance from angle to angle of mouth below 10-50 



„ between the pectoral flippers, under surface . . . . . .9-00 



Measurements of two specimens of Orcella Irevirostris. 



From tip of snout to caudal notch, alongside 

 Snout to dorsal fin following curve of back 

 Length of the dorsal fin {i. e., antero-posteriorly) 

 From tip of snout to base of pectoral flipper 

 Length, anterior margin of pectoral extremity 



„ posterior margin of same . 

 Caudal fin along its anterior border 

 Snout to blow-hole over forehead . 

 Breadth of the blow-hole 

 Height of the dorsal fin . . , 

 Across from tip to tip of caudal fin 

 Depth of the caudal notch 

 Length of pectoral extremities in a straight line 

 Greatest breadth of pectoral flipper 

 From the tip of snout to angle of mouth 

 From angle of mouth to ear-hole in straight line 

 Distance between angle of mouth and eye 

 Length of the eye ...... 



Distance from eye to eye taken round point of snout 



I ? 



II 9 



Inches. 



82-50 



46'00 



8*00 



16-50 



17-00 



12-00 



16-00 



10-00 



1-50 



3-75 



21-50 



1-75 



14-00 



6-25 



6-00 



4-75 



1*63 



0-87 



15-00 



Inches. 

 71*00 



42-00 



5*00 



15-75 



15-75 



11-52 



13-25 



9*10 



1*33 



2*25 



2000 



1-50 



13*25 



5-75 



5-75 



4-50 



1-33 



067 



13-50 



Cavity of the mouth {?\,^^Yll,^g^. 1 & 2).— The pigment of the external 

 skin occurs on the mucous membrane as far as the position of the frsenum lingua, 

 on the inside of the lower lips, and all over the upper lips and on the palate as far 

 back as on a line with the angle of the mouth. The lower lip is rounded, but the 



