114 MERISTIC VARIATION. [part i. 



have been expected had there been an even Homceosis throughout 

 the dorso-lumbars.] 



Male, cet. 50. C 7, D 12, L 6, S 5, C "3 or 4, probably 4." 

 Thirteen pairs of ribs, 13th ribs on 20th vertebra, nearly sym- 

 metrical, right 2 in. long; left 1J, and in breadth a little less than 

 the right. The 6th lumbar, 25th vertebra, had the characters of 

 a normal last lumbar (sc. 24th vertebra), including normal trans- 

 verse processes. Coccyx in 3 moveable pieces, the 3rd apparently 

 composed of two. There is therefore probably one more than 

 the normal number in the whole series. Struthers, J. Anat. 

 Phys., 1875, p. 62. 



27. Male, cet, 56. C 7, D 12, L 6, S 5, C 3. Dorsal vertebrae and 

 ribs normal. 20th vertebra normal, except that it has no trace 

 of transverse processes ; ribs have perhaps been present on it. 

 25th vertebra quite free from sacrum, but articulating with ilium 

 by small facet on each side. The 1st coccygeal joined to sacrum. 

 Struthers, I. c, p. 66 and p. 91. [Homceosis in absence of trans, 

 processes in 20th vertebra, in separation of 25th from sacrum, and 

 in union of 30th with sacrum.] 



28. Skeleton C 7, D 12, L6, S 5, C lost. The 25th vertebra is separate 

 from the ilium and the sacrum, but the 30th is united to the latter. 

 Struthers, I.e., p. 69. 



29. Male, cet. 29. C 7, D 12, L6 (1st bearing ribs — 6th partially joined 

 to sacrum), S 5 (exclusive of 5th lumbar), C 4. 20th vertebra bearing 

 ribs ; 25th partially free from sacrum but partly supporting the ilium, 

 and one extra vertebra in the series. Struthers, I. c., p. 64 and p. 92. 



30. Skeleton D 12, L 6, S 4, C 4. The 25th vertebra by right trans- 

 verse process articulates with sacrum and on the same side with the 

 ilium ; the 30th, however, though moveable on the sacrum, has charac 

 ters transitional between those of a 5th sacral and a 1st coccygeal. 

 Struthers, I.e., p. 68 and p. 91. 



31. Male. C 7, D 13, L 5, S and C ankylosed together of uncertain 

 number. Articular processes change between 20th and 21st, i.e. a space 

 lower than usual, but the processes between 19th and 20th are smaller 

 than those higher up and are not quite symmetrical. The 20th vertebra 

 bore rib on left side and rib has apparently been present on right, but 

 probably not so much developed. Struthers, /. c., p. 64, note. [For- 

 ward Homceosis in development of ribs on 20th and in detachment 

 of 25th.] 



But though the variations of the vertebrae may thus in great 

 measure be reduced to system, there remain other cases, rare in 

 Man but not very uncommon in lower forms, which cannot be 

 brought into any system yet devised. Such cases shew that the 

 limits imposed by a system of individual homologies, between which 

 we conceive the occurrence of Variation, are not natural limits, 

 and that they may be set aside in nature. In the following case it 

 may be especially noted that Variation in the segmentation of the 



