82 ANATOMICAL NOTES ON MALAY APES. 



mana is in a plastic condition, and the great development of the 

 pectoral muscles — especially the manubrial portion of them — 

 may determine the union of the first and second parts. 



The sixth centre of sternal ossification appears late in juve- 

 nile life in the Semnopitheci, and in one adult it had failed to 

 put in an appearance (see diag. VIII). 



(b) — Variations in Ribs and Chest Walls. 



In the same genus the eighth pair of ribs seem undecided 

 whether they should terminate in the fibro- cartilage in front 

 of the xiphoid or not come within an inch of it (see diags. VI, 

 VII, VIII, IX, X). In Papio nemestrinus the eighth pair of 

 ribs always reach the sternum (see diag. VIII). In a speci- 

 men of Semnopithecus the fifth rib ' terminated in a piece of 

 cartilage to which some fibres of the diaphragm were attached 

 (see diag. VI). In three specimens of the same genus, I 

 came across rib-like developments in the fifth, sixth and 

 seventh costal cartilages (see diag. VIII), and in all the adults, 

 these cartilages were more or less ossified. 



There are three floating ribs as a rule in Semnopitliecus, 

 but in two specimens the tenth rib had joined those above and 

 become a false rib. 



(c) — Variations in the Lumbar Region. 



In a foetus of Papio nemestrinus, I found the transverse 

 process of the first lumbar vertebra enlarged and representing 

 a thirteenth rib. It was costal in dimensions and appearance 

 (see diag. XI). There was a similar condition in the second 

 lumbar vertebra of Hylobates lar, representing a fourteenth 

 rib (see diag. XII). 



In the gibbon the twenty-sixth vertebra affects the chief sup- 

 port of the pelvic bones, while in the monkeys and baboons it 

 is the twenty-seventh. Diag. XV shows the peculiar condition 

 found in one of the Semnopitheci, on one side the twenty- 

 seventh as usual is supported by the pelvic bones, but on the 

 other side it is the twenty-eighth, the twenty seventh on that 

 side having a plain transverse process. Professor G. B. HOWES 

 (Journal of Anatomy, July, 1890) shows a similar condition in 

 a frog (diag. XIV). The above-mentioned specimen shows 



considerable aggregations of cartilage on its twentv-fifth and 



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twenty-sixth transverse process as if at one time they had 



