352 Dr. J. E. Gray on the Whalebone-Whales. 



3. Physalus. 



The second cervical vertebra with a broad expanded lateral 

 process, with a large perforation in the upper part of its base. 

 The first rib with a simple compressed head, and with a com- 

 pressed internal process near the condyle. Lower jaw-bones 

 thick, convex on the sides, with a distinct conical coronoid pro- 

 cess. Ribs 14- to 16. Vertebrre 60 or 62. 



1. Physalus antiquorum, Gray, Proc. Zool. Soc. 1864. 



The lateral processes of the 3rd, 4th, 5th, and 6th cervical 

 vertebrse broad, ring-like ; the lateral processes of the 2nd cer- 

 vical elongate, oblique, truncated. Ribs 14 . 14. 



Hah. Northern Seas. Skeleton, Mus. Brit, and Alexandra 

 Park. 



2. Physalus Duguidii, Gray, Proc. Zool. Soc. 1864. 



Ribs 15 . 15. 



Hab. Northern Seas ; Orkney. Cervical vertebrse, Mus. Brit. 



3. Physalus Sibbaldii, Gray, Proc. Zool. Soc. 1864. 

 Ribs 16 . 16. Ramus of lower jaw conical, high. 



Hab. North Sea; mouth of the II umber. Skeleton in Hull 

 Museum. 



4. SiBBALDUS. 



The second cervical vertebra with a broad elongated lateral 

 process, perforated at the base. The first and second ribs double- 

 headed. Lower jaw-bones compressed, high, flat on the sides, 

 with a distinct conical coronoid process. Vertebrse 55. Ribs 

 13 or 14. Arm-bones slender. 



1. Sibbaldus laticeps, Gray, Proc. Zool. Soc. 1864. 

 Balcenoptera laticeps, Gray ; Lilljeborg, I. c. p. 63. 

 Ribs 13 . 13. Dorsal fin compressed. 

 Hab. Northern Seas. Skeleton, Mus. Berlin. 



2. Sibbaldus Schlegelii. 



Balanoptera from Java, Schlegel, Mus. Leyden. 



B. Schlegelii, Flower, MS. 



" Megaptera from Java," Van Beneden, Gray, Proc. Zool. Soc. 1864, p. 20g. 



Hab. Java. Skeleton, Mus. Leyden (young); skull, Mus. 

 Leyden. 



3. Sibbaldus borealis, Gray, Proc. Zool. Soc. 1864. 

 Balanoptera gigas, Reinhardt & Lilljeborg. 

 Ribs 14 , 14. Dorsal fin small, far back, on a prominence. 

 Hab. Northern Seas. Skeleton. 



