A PECULIAR PELVIC ATTACHMENT IN NECTURUS 



MACULATUS. 



CLARA HEPBURN. 



While studying the vertebral column of Nccturus inacnlatns, 

 in the regular class work, I found in my specimens a peculiar 

 form of pelvic attachment which seems remarkable enough to 

 mention. 



The pelvis was attached to the eighteenth vertebra and, in ad- 

 dition, there were two rudimentary ribs on the nineteenth. There 

 was nothing strange about the twentieth but on the twenty-first 

 there was one half of a haemal spine, that of the right side, the 

 first complete haemal arch being on the twenty-second. 



For comparison in order to show its anomalous character, it 

 is necessary to give the statistics concerning the conditions as 

 reported hitherto. F. Smith, 'oo, and Wilder, '02, have summa- 

 rized the results hitherto reported, including the papers of Parker, 

 '96, Bumpus, '97, and Waite, '97. 



In one hundred and fourteen specimens tabulated by Smith, 

 the sacral vertebra was the nineteenth in eighty-one cases, the 

 twentieth in sixteen and the twenty -first in one, this latter being 

 the most posterior position ever recorded. In twelve cases the 

 pelvis was oblique and of these three made use of the eighteenth 

 on one side. In four cases there were three sacral ribs, that is, 

 two upon one side and in one of these, figured by Smith on page 

 638, the ribs involved were the eighteenth on the right and the 

 eighteenth and the nineteenth on the left. Thus in Smith's one 

 hundred and fourteen cases, four involved the eighteenth ver- 

 tebra but all were asymmetrical. The one which approached 

 nearest my specimen is the one figured by Smith, where there 

 was a ligamentous connection between the rib rudiment on the 

 nineteenth and the sacrum, and as my specimen had been macer- 

 ated before I examined it, I cannot tell whether there was such 

 a connection or not. 



As Wilder has used the same authors for his summary as has 

 Smith, it is unnecessary to give his report. 



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