26 Development of the Bones. 



2. 42. Development of Thorax. — Cervical and upper ten 

 dorsal vertebrae, with corresponding ribs and sternum, from a 

 foetus, probably about the fifth month — injected, cleaned, and 

 in spirit. 



The shape of the parts is exceedingly well seen. 



B. C. 1. N. 78. 



2. 43. Development of Sternum.— Sternum of a foetus, about 

 the fourth month — in turpentine and injected. Three points 

 of ossification are seen. B. C. 1. N. 80. 



2. 44. Development of Sternum. — Sternum of a foetus of about 

 the eighth or ninth month — injected and in turpentine. 



Three large and three smaller points of ossification are 

 now seen. B. C. 1. K 81. 



2. 45. Development of Sternum. — Sternum and costal cartilages 

 of a child at birth — in spirit — showing four centres of ossi- 

 fication in the former. B. C. 1. N. 82. 



2. 46. Ossification in Sternum. — Sternum in which the 

 ossification is nearly complete, but still showing the double 

 centres in the third, fourth, and fifth pieces. B, C. 1. N. 84. 



2. 47. Development of the Bones of Upper Limbs.— Bones 



of the arms of a foetus under the third month — prepared and 

 dried, so as to show the amount of ossification at this time. 



B. C. 1. N. 90. 



