300 



THOMAS DWIGHT ON 



transverse processes of the 7th vertebra is distinctly greater than that of the 1st thoracic. 

 The slender neck of the 1st I'ib is uncommonly long ; the transverse diameter of the costo- 

 transverse foramen being about 17 mm. This specimen is a very striking demonstration 

 of Leboucq's view ('96-98) that the cervical costal element is the piece of bone between 

 the two tubercles. In the 7th vertebra the anterior tubercle is rudimentary, so that the 

 costal element is relatively long and nearly transverse. In the 6th and those above it the 

 costal element is short and directed more backwards, being the floor of the groove in 

 which the nerve lies. The gradations are shown remarkably clearl}'. The 6th cervical is 

 also remarkable. The foramen on the right is double. The anterior, which presumably 

 is the costo-ti'ansverse, is not quite round. It measures ti'ansversely a little over 6 mm., 

 and a little less antero-posteriorly. The transverse foramen, almost directly behind it, 

 measures nearly 4 mm. On the left tlie foramen is large, measuring nearly 1 cm. in 

 diameter. There is some indication of a notch at the posterior outer aspect, as if another 

 were partly cut off from it. The foramen on the right of the oth vertebra shows at the 

 back a distinct attempt at a subdivision. 



Rudimentary First Ribs. 



140. Cat. !:)o79.o8. — Male, white, aet. 38. A ligamentous preparation of the last two 

 cervical and the first four thoracic vertebrae, with ribs and manubrium. The first rib on 

 the right is smaller than usual, especially at the part be3'oud the tubercle. It reaches to 

 about 2.5 cm. from the sternum and is then contiuued by cartilage which contains a large 



distinct calcified piece. The left cor- 

 responding ril) is much smaller. It 

 is strongly curved. The head, neck, 

 and tubercle are not excessively small, 

 though smaller than those parts of the 

 right rib. The distance from the 

 outer edge of the tubercle to the tip 

 in a straight line is -j.(» cm. The 

 Ijreadth near the front is imder 1 cm. 

 It ends free more than 4 cm. from 

 tlie inanulniiun. Whether, as is most 

 probable, it was connected by liga- 

 ment, I am unable to say. The next rib is very like a normal 'id one, excepting in its 

 insertion. The cartilage extends aU along the side of the manubrium, and from the 

 upper part of this cartilage there is a short projection towards the rudimentary rib. The 



140. 



