272 DELPHTNID^E. 



the beak, concave on the sides, and keeled in the middle behind. 

 Teeth A}} ?, very slender, curved, elongate, conical, tapering, acute ; 

 the front one very small. 



Lagenorhynclms Thicolea, Gray, Proc. Zool. Soc. 1849 ; An». ^- May. 

 N. H. 1849, V. 48 ; Zool. Erehm ^- Terror, t. 36, ined. (skull) ; Cat. 

 Cetac. B. M. 1850, 103. 



Inhab. West coast of North America. 

 a. Skull : imperfect behind. From Dr. Dickie's Collection. 



in. lin. 



Length of skull, entire 14 6 ? (end of nose injured). 



Length of beak 8 4 



Length of teeth-line 7 



Length of lower jaw 12 3 (entire). 



Width at orbits 7 



Width at notch 3 11 



Width at middle of beak 2 2 



Width of intermaxillary at middle .^ . 12 

 Width of condyles 3 



I • \ b. Beak moderate. Rostrum of skull only as long as the brain-case. 

 . ') Teeth not quite to the 7iotch. 



\ ^i) ' 8. Lagenorhynchus albirostris. White-beaked Bottlenose. 



\ /f ' Upper part and sides very rich deep velvet-black. External cuticle 



soft and silky, so thin and delicate as to be easily rubbed off. Nose, 

 a weU-defined line above upper jaw, and the whole under jaw and 

 belly cream-colour, varied with chalky white ; fins and tail black. 

 Teeth |^, small, curved. Jaws moderately elongate, lower rather 

 the longest. Blowhole horseshoe-shaped and convex towards the 

 head. Nose of skull as long as the brain-case, gradually and evenly 

 tapering to a rather rounded point in front, the edge rather reflexed 

 on each side behind. The triangle in front of the blower convex 

 and swollen on each side behind, smooth in front. 



Delphinus Tm-sio, Brif/htiveU, Ann. Nat. Hist. 1846, 21. t. 1 $. 



Delphiniis albirostris, Gray, Ann. ^- Mag. N. H. 1846 ; M. Clausen, 

 Dissei't. de LagenorhyncMs, Kilice, 1853. 



LagenorhjTichus albirostris, Gray, Zool. Erebus ^ Terror, t. 10 (ani- 

 mal, from BrightwelVs drawing), t. 11 (skull), 1846. 



Delphinus pseudotursio, Reichenb. Cetac. t. 24. f. 7, 6, cop. Brightwell. 



Delphinus (Lagenorhjuchus) albirostris, Van Beneden, Xouv. Metn. 

 Acad. R. Brtu: xxxii. 1. 1, 2 (animal, skeleton, and viscera). 



Var. ? Teeth smaller, ||^. Beak narrower. 



Delphinus Tbsenii, Eschricht, Undersogelser over Hvaldyrene bte Afh. 

 73; uchd. Ss.foredrag rid Katurforsk.7ndtet.iKpbenh.l84:7 ; Nilsson, 

 Skand. Fauna, i. 600. 



Inhab. North Sea, Faroe Islands. Yarmouth, 1846 {Brightwell) ; 

 skeleton in British Museum ; skull figured in ' Zool. E. and T.' 11. 

 Ostend, July 1851, female. Winter 1852, female {Van Beneden, 

 I. c. p. 20). 



i, 



