116 MERISTIC VARIATION. [part r. 



pelvis. Whichever view be taken, this case is an interesting one, 

 as exhibiting variation in every region of the spine, and as shewing 

 the importance of examining the entire spine before deciding as to 

 a variation of any one part of it." 



To the question, which vertebra is missing, there is no answer ; 

 or rather the answer is that there is no segment in this body 

 strictly corresponding to the normal 7th, 20th, 25th, &c; that the 

 characters of these several segments are distributed afresh and 

 upon no strict, consistent plan among the segments of this body, 

 and that, therefore, there is no one segment missing from the 

 body. Surely further efforts to answer questions like these can 

 lead to no useful result. 



Attempts to interpret Variation by the light of simple arith- 

 metic serve only to obscure the real nature of Repetition and 

 segmental differentiation ; for by constantly admitting to the 

 mind the fancy that this simple, subjective representation of these 

 processes is the right guide, and that the tangible complexity in 

 which they present themselves is a wrong one, we only become 

 used to an idea which is not true to the facts and the real difficulty 

 is shirked. 



Anthropoid Apes. 



Though adding little that is new in kind to the foregoing speci- 

 men-cases occurring in Man, the following instances of Variation 

 in the vertebrae of the Anthropoid Apes are of some interest if only 

 as illustrations of the fact that the frequency of such Variation 

 has no necessary relation to the conditions of civilization or domesti- 

 cation. (On the subject of Variation in the vertebrae of Anthropoids, 

 see especially Rosenberg's list, Morph. Jahrb. I. p. 160.) 



Troglodytes niger (the Chimpanzee). 



[In considering cases of variation in the Chimpanzee it should 

 be borne in mind that there are several races and perhaps species 

 included under this name, which have not been clearly distinguished. 

 It is possible, therefore, that some of the variations recorded may 

 be characteristic of these races and not actually individual varia- 

 tions.] 



C 7, D 13, L 4, S 5. 



This is the formula in the great majority of Skeletons (v. auctt.). 

 33. An adult female having C 7, D 12, L 4, S 5, C 5, viz. one 

 vertebra and one pair of ribs less than usual. This is a specimen 

 of du Chaillu's T. calvus. It was received united by the natural 

 ligaments and no vertebra therefore is lost. Gat. Coll. Surg., 1884, n. 

 No. 4. 

 34 # Specimen having rudimentary ribs unequally developed on the 

 21st vertebra. The 25th vertebra was transitional or lumbo-sacral in 

 character. The 26th — 30th formed the sacrum and there were 6 

 caudals, while other specimens had from 2 to 4. For the lumbo- 

 sacral plexus of this specimen, see No. 71. Rosenberg, Morph. 



