OTARIID.E, PHOCID^E, MUSTELID^, PROCYONID^, AND URSID^J. 251 



obtuse bisectrix (text figure 259) . Looking along a the biaxial figure is seen with moder- 

 ately separated brushes, and the axial angle 2E r =37 to 40 as measured in white light 

 (nearly monochromatic and red owing to the color of the crystal). The axis of greatest 

 elasticity is, therefore, the acute bisectrix Bx a = a, and the optical character is negative. 



The trillings of the oxyhemoglobin and CO-hemoglobin of the Cali- 

 fornia sea-lion noted above are apparently perfectly conformable with 

 trillings observed in different species of the Ursidce (page 259) . In the case 

 of the California sea-lion, however, the axis of the trilling was taken as the 

 crystallographic axis a; in the case of the Ursidce as the axis c. In order 

 better to compare the oxyhemoglobin and the CO-hemoglobin in the Otari- 

 idce and the Ursidce the crystals of the sea-lion were recalculated, regarding 

 the trilling axis as 6, as follows : 



Oxyhemoglobin of Otaria gillespii. 



Monoclinic sphenoidal (tartaric acid type) : Axial ratio a : b : c =1.8019 : 1 : 0.7883; 

 /3=74. 



Forms observed : Unit pyramid (Til); unit prism (1TO) ; orthopinacoid (100) ; clino- 

 dome (Oil); base (001). 



Angles : Traces of unit pyramid on orthopinacoid, edges llT-100ATll-100 = 103 30' ; 

 opposite pole traces of clinodome on orthopinacoid edges OTl-100 A 011-100 = 103 30'. 

 Angle of prism 1TO A TTO=60 from twins. Orthopinacoid to base 100 A001 =74. 



In this orientation the habit is tabular on the orthopinacoid elongated on the ortho- 

 axis (text figure 261), instead of being tabular on the base, as in the original orientation. 

 The orientation of the elasticity axes is a = (! very nearly; b=b; c A a = 16 30', in the 

 obtuse angle; the axis c is nearly or quite normal to the orthopinacoid. The plane of 

 the optic axes is the clinopinacoid 010, Bx a = a, and the optical character is negative. 

 The axial angle 2=35 to 40. 



CO-hemoglobin of Otaria gillespii. 



In the changed orientation of the CO-hemoglobin crystals the descrip- 

 tion is entirely analogous to that of the oxyhemoglobin. 



263 



FIGS. 261, 262, 263. Otaria gilUipii Oxyhemoglobin (second orientation). 



Text figures 258, 259, and 260 are drawn according to the original 

 orientation; text figures 261, 262, and 263 according to the orientation as 

 revised. 



In the summary of the crystallographic characters of the hemoglobins 

 of the Phocidce, Otariidce, Mustelidce, and Ursidce, page 263, the axial ratio 

 of the oxyhemoglobin and CO-hemoglobin of Otaria gillespii is entered 

 according to the second orientation ; the isomorphism between the crystals 

 of oxyhemoglobin of this species and those of Ursus americanus and Ursus 

 maritimus is there apparent. 



