SVENSKA EXPEDITIONEN TILL MAGELLANSLÄNDERNA. ED. II. N:0 7. 15D 



pact as those of the Mylodonts. The bloodvessels are very 

 numerous and their canals are very wide and mnch branched 

 so that the main structure of these scutes becomes rather 

 spongy. Fibrils of connective (Sharpey's fibrils) tissue are 

 not entirely wanting in the scutes of Dasypus, but much less 

 developed than in the ossicles of the Mylodonts. They are 

 ebierly found at the edges of the scutes, and near and at the 

 proximal surface, and are not collected into such bundles as is 

 described above in the •»Neomylodon» ossicles. Pigraentcellu]es. 

 are not to be observed in the scutes of Dasypus. 



The difference in structure between the scutes of Dasypus 

 and the ossicles of »Neomylodon» is thus very pronounced, and 

 may, at least partly, be caused by the different Situation of 

 the resp. organs. The former lie close to the epithelial tis- 

 sue and can be considered as modified parts of the cutis, the 

 latter, on the other liand, are not situated so superficially. 

 Although bordering the cutis and more or less deeply sunk 

 into it they belong more to the looser subcutanean tissues 

 in which they are chiefly imbedded. This has already been 

 pointed out above when describing the piece of skin No. 5 

 and can be seen on the figure of the same. But it can also 

 be seen on fig. (> representing a view of a freshly cut margin 

 of the skin piece No. 6. There we see an outer denser layer 

 of a darker shade, and an inner looser Stratum which is 

 lighter and in which the ossicles lie. It is possible that the 

 ossicles of Mylodon have been situated a little more super- 

 ficially than those of the »Ncomylodon». The small round de- 

 pressions on the surface of the former might possibly hint at 

 such a thing, then it could be supposed that they corres- 

 ponded to the follicles and papillee of soine large hairs. 

 But even if that should have been the case they have not 

 been placed so close to the surface as the scutes of Dasypus 

 in which the hair follicles and the, to them belonerine:, sdands 

 are very deeply implanted in holes before they get destroyed 

 by the ossification. 1 There is another thing which must also 

 be remembered when discussing these organs. Römer has shown 

 (1. c.) that the horny scales and shields of the Dasypodhhr 

 are ontogenetically the primary organs, and the bony scutes 

 originate through a secondary ossification of the Cutispapil- 



1 Conf. Römer, Über d. Bau u-. d. Entwickelung d. Panzers d. Gürtel- 

 tiere, Jenaische Zeitsehr. f. Naturwiss. Bd. 20 (27). Jena. 1892. 



