12 PKOCEEDINGS OF THE NATIONAL. MUSEUM vol. 70 



to that of the fourth, fifth, and sixth vertebrae, is also quite variable. 

 This seventh vertebra has a costal facet for the capitular attachment 

 of the first thoracic rib. 



Allen writes (p. 250) that in all five of the specimens which he 

 examined, as well as in Temminck's example, there was a pair of small 

 accessory ribs in connection with the seventh cervical. In 240864 

 there was a pair of these cervical ribs attached by syndesmosis or 

 shreds of fibrous tissue to the ventral aspect of the transverse proc- 

 esses of the seventh vertebra of this series. Careful search during 

 dissection for cervical ribs in 240862 was without result. In the 

 skeletons before me there are a number of bone fragments consisting 

 of small pieces of broken ribs, chevron bones, and of processes of the 

 vertebrae. Indistinguishable from these are doubtless some cervical 

 ribs; but the only ones in which the latter may be identified as such 

 with satisfactory certainty are as follows: No. 240001, one (19 mm.) ; 

 240002, two (19.2 and 18.5 mm.) ; and 49544, one (lY mm.). 



Pig. 5. — Cervical vertebrae of neombris : A, dorsal view 



FACING CAUDAD ) B, LATERAL VIEW OF RIGHT SIDE 



Thoracic vertehrae. — The fact that five of the skeletons examined 

 have but 12 thoracic vertebrae, which is a smaller number than here- 

 tofore recorded for this genus, is somewhat surprising. All of those 

 considered by Allen had 13 save the one reported by Lydekker, which 

 had 14. But one of the animals studied by me has 13 vertebrae in 

 this series, while one (No. 240864, which was not cleaned) has 14. 

 This series varies from 24 to 25 per cent of the total vertebral length. 



The homology of certain of the vertebral processes of the Cetacea 

 is a matter of some dispute, but the question certainly can not be 

 settled until a thorough study of all known fossil as well as recent 

 forms has been made. In those cetaceans in which the serial transi- 

 tion of the lateral vertebral processes is abrupt, as Hyperoodon and 

 Mesoplodon, the question of homology is a different matter, which 

 does not here concern us; but in Neomeris, which in this respect is 

 comparable to the majority of whales, the conditions are tentatively 

 believed to be as follows: 



The centra of the first six thoracic vertebrae, as well as the seventh 

 cervical, have facets for the capitular attachment of the first seven 

 cervical ribs. There are no certain indications of parapophyses asso- 



