16 FISCHER ON THE PELYIS OF THE MAMMALIA. 



height and thickness as those of the lumbar and dorsal vertebrae, so that the 

 passage of the one into the other cannot be perceived. The nine-banded Tatu 

 has three sacral vertebrae. 



Section 13. The os coccygis of the bradypi-didactylus has eight vertebral ; 

 the nine-banded tatu, 28 ; the myrmecophega didactylus, 42. 



Section 14. Ossa innominata. The internal surface of the os ilium is 

 curved in the middle, and has three smaller surfaces, a superior, inferior, and 

 internal ; the former are broad, the internal narrow. The external surface is 

 concave. The pubic bones of the myrmecophega didactylus have an opening 

 between them of a line and a half in extent. (Whether this hiatus, spoken of 

 as occupying the place of the symphysis pubis be real or not, is still to me very 

 doubtful ; in the skeleton of the European hedgehog, when freed of all soft 

 matter, the bones of the pubis have a gap between them of two lines and 

 more, but along a slender cartilage, which placed transversely forms the 

 symphysis in that animal, cannot escape the notice of the more careful observer. 

 The pelvis of the leasypus shews another form of the pelvis meriting notice, 

 and which will be described a little further on. Autenreith.) 



Section 15. 4. Chiroptera. The vespertilio caninus, and the murinus, have 

 each four sacral vertebrae, but the caninus has three coccygeal vertebrae, the 

 murinus has ten. The seventh of these is larger than the others, and is four 

 lines long. Pallas * says of the vespertilio cephaloteide, that the bones of the 

 pelvis are slender, and do not meet at the pubis, lest this narrowness interfere 

 with the birth. In the caninus the os ilium is not three sided, as in the muri- 

 nus, but its external surface is very convex. Above the acetabulum there is a 

 very large spine. In the caninus the ossa pubis are slender, and meet each 

 other ; it is the same in the murinus. In the caninus the foramina ovalia are 

 broader than long. The bodies (tuberosities ?) of the bones of the ischium in 

 the vespertilio vampyre are plain, with cleft margins united together ; thus the 

 posterior aperture of the pelvis shut in by a continuous margin, is oval, the 

 horizontal branches of the bones of the pubis alone (angles between the hori- 

 zontal and descending branches alone ? A.) forming the symphisis and uniting 

 into a half circle, f The pelvis of the vespertilio murinus is remarkable for 

 the spinous tubercle of the os pubis extended into a very long spine. Accord- 

 ing to the drawing of Meyer this spine ascends still higher, so as to seem to 

 form a complete foramen, with a horizontal ramus of the os pubis, perhaps 

 joined by a ligament to the os ilum by its apex. To the spine the ligament of 

 Poupart is admitted by all to be attached. I could find neither this ligament 

 nor the perfect abdominal ring in the male masupialis didelphis ; the vessels 

 and crural nerves proceeded unprotected beneath the small accessory bones and 

 the margin of the acetabulum ; so that that little bone, which shuts in the ab- 

 dominal pouch in the didelphis, seems to me nothing else than the spine of the 

 pubis, composed of that little bone itself and its articulation with the hori- 

 zontal ramus of the pubis joined together. But this spine of the pubis seems 

 to arise simply from the ossification of the end of the ligament of Poupart, as 

 the tendons become ossified in the feet of birds, and so are united to the 



* P. S. Pallas spicilegia zoologica. Fasc 3. Berol, 1787, p. 23. 



t Cfr. G. F. Herman Disser. Observations et anecdota ex osteol, comp. Argent, 

 1792, 4. p. 12. 



