376 MESE GEORGE MIVART ON THE VERTEBRATE SKELETON. 
ribs in certain vertebrates ; and it may be termed the lower transverse process, or the 
capitular process, or the parapophysis (fig. 2, c, & fig. 14) *. 
This (according of course to the same conception) is continued outwards by the ribs, 
and is often completed inferiorly by skeletal structures which, when ossified or chondrified, 
are termed sternal, i.e. sternal ribs and sternum proper (fig. 2, sr & s). 
Thus we may have complete coalescence proximally of the upper and lower paraxial 
elements, and then we have a simple transverse process; or we may have a simple trans- 
verse process essentially diapophysial, because in series with the tubercular processes of 
vertebree in front, as in Delphinus; or we may have an apparently quite similar trans- 
verse process essentially parapophysial in nature, because in series with the heads of the 
ribs of vertebræ in front, as in Physeter. 
These distinctions, as they exist in the Cefacea, were pointed out by Professor Flower 
in his recent Hunterian Course. 
Very often, as in so many fishes, the parapophyses and ribs of the trunk are repre- 
sented in the tail by a single continuous ossification which answers to both. Thus the 
ribs of most vertebrates, according to this view, would be of essentially complex 
nature, and consist of an ossification which has taken place in the line where the upper 
and lower paraxial elements have coalesced. Amongst fishes, the Carp appears to have a 
single series of ribs into which both elements enter. It must be recollected that this 
conception is thrown out only as a suggestion. 
It might be objected that the parts here treated as more or less distinct are often 
merely outgrowths one from the other. But this is no objection to the view that the 
form described is the one that the skeleton tends to assume, and actually does assume 
more or less completely. However solidification be attained, the tendency to solidify m 
these particular lines must preexist in the soft tissues. From the frequent point of 
origin of the diapophysis it is manifest that we often have coalescence or connation 
between paraxial and epaxial parts, ¿. e. between the transverse process and neural arch’ 
yet they are accounted distinct. 
The “chevron bones” and caudal hemapophyses of Probes Owen belong, I believe. 
to an altogether different skeletal category. 
3. What is the essential nature of branchial arches, and in what relation do they 
stand to ribs ? 
These arches have been regarded by Carus and Professor Owen as forming part of 
the splanchno-skeleton, and therefore as altogether distinct in nature from the vertebral 
and sternal ribs, and, indeed, constituting no part of the true endo-skeleton. 
Professors Goodsirf and Huxleyt, on the other hand, take them to be the serial 
homologues of the thoracic or abdominal ribs, and therefore consider them what I call 
* Though Professor Owen originally employed this term to denote a process essentially autogenous, now, how- 
ever, he regards it as normally exogenous. See‘ Anatomy of Vertebrates,’ vol. i. p. 28. 
T See * Edinburgh New Phil. Journal, vol. y. New Series, p. 131. 
+ “ Hunterian Lecture ” for 1869, see ‘ Brit. Med. Journal, No. 443, June 26, 1869, p. 589. 
