. On the anatomy of vertebrates [electronic resource] . Of the seven cervicalthe first two only are anchylosed: thir-teen vertebrae support free ribs suspendedto terminally expanded diapophyses, , r/; then follow twenty-nine with trans-verse processes only, as in fig. 141, d : thethirty-third vertebra from the skull firstsupports a haemal arch, but in that andthe two following vertebrae the piers or6 haemapophyses are small and ununited:the complete arch, as in fig. 282, h, iscontinued, diminishing, to the last sixvertebrae, which consist of the centrumonly, much depressed. Thus, betwee
. On the anatomy of vertebrates [electronic resource] . Of the seven cervicalthe first two only are anchylosed: thir-teen vertebrae support free ribs suspendedto terminally expanded diapophyses, , r/; then follow twenty-nine with trans-verse processes only, as in fig. 141, d : thethirty-third vertebra from the skull firstsupports a haemal arch, but in that andthe two following vertebrae the piers or6 haemapophyses are small and ununited:the complete arch, as in fig. 282, h, iscontinued, diminishing, to the last sixvertebrae, which consist of the centrumonly, much depressed. Thus, betweenthe thirteenth dorsal vertebra and thefirst with haemapophyses, there are thirteen which might betermed f lumbar, fig. 159, D, cd, but hold the place of lumbar andsacral in other Mammals (Megatherium, , fig. 279, L, s). Asacrum is never indicated by vertebral confluence in Cetacea, andonly obscurely by the position of the pelvic rudiments, fig. 159,63, 64, loosely suspended below. In the Delpli. tursio a metapo-1 xenr. 2 xviii*. p. 520, fig. Caudal vertebra, Whale. SKELETON OF CETACEA. 417 physis begins to project from the fore part of the diapophysis ofthe third dorsal, increases in length to the fourth, and is graduallytransferred in the sixth and seventh dorsals to the outer side ofthe prozygapophyses : in the following vertebra? it seems to taketheir place, and to occasion a reversing of the usual relative posi-tion of the zygapophyses; for whereas in the cervical andanterior dorsal vertebras the anterior ones are overlapped, as inother Mammals, by the posterior zygapophyses of antecedentvertebrae,—in the succeeding dorsals, beginning with the seventh,the posterior zygapophyses seem to be overlapped and con-cealed by the anterior ones ; but the appearance is due to theplace of the zygapophyses being taken by the latter processes, in fact, continue after the articular surfacehas ceased to be developed, and after the entire disappearance ofthe
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