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1-0 MR. J. C. GALTON ON DASYPUS SEXCINCTUS. 



terminates at this latter the tendon of a slightly flattened fusiform muscular slip, which 

 arises from the bottom of the coronoid fossa of the humerus, and proceeds straight 

 towards its insertion. 



From the anterior extremity of the sesamoid proceed four very stout tendons to each 

 of the four inner digits ; while from its radial side, a little posterior to the origin of the 

 above tendons, a tendon, having a much smaller diameter than these, is given off for the 

 pollex, and is finally inserted into the base of its ungual phalanx. 



Each tendon, before being inserted into a strong spinous projection at the base of the 

 palmar aspect of the ungual phalanx of its proper digit, passes over an oval, flattened 

 sesamoid, which lies at the junction between the ungual and preceding phalanx. 



Posterior to the large sesamoid bone, a strong retinaculum springs up from the bottom 

 of the sheath (regarding it from its palmar aspect) to join the deep flexor tendon. 



Meckel states that the flexor profundus goes to the three outer digits ; and mentions 

 also that its tendon contains a sesamoid bone 1 . 



In the Echidna, as in the Ornithorhynchus," says Mr. Mivart, " there are one or two 

 ossicles in the palmar portion of the flexor tendon" 2 . 



Meckel, in his monograph upon the latter Monotreme 3 , says, in the course of the 

 description of the deeper of the fore foot, « tendine crassissimo, cujus fini inferiori duo 

 ossicula, ad Saunorum Dasypodumque modum, insunt." 



The Chbrmyphorus has a palmar sesamoid very much resembling in shape that of 

 Dasypus sexciact^; while in Priodontes (Dasypus) gigas this bone is very large, and 

 ot an irregularly conical shape, the apex being directed forwards 5 



Pronator aitadratus.--^ muscle appears to be completely absent It is not figured 

 by Cuvier m his plates of the myology of Ba W s. Meckel notices the absence of this 

 muscle m the «Tatu,» but remarks that the pronator teres is well developed in com- 

 pensation. He states, too, that in the Ai it is very small, perhaps smaller than in any 



c< 



; « Ein starker, spiiter unstreitig verknocherter Faserknorpel."-^ c iL p. 560. 



footnote : 



inatomy of Echidna Hystrix 



.. 



1^ tlT • r' mar ° SiCle ?' 30 6Xi8ta in thc A ™* : «d ^feasor Huxley 



following 



Hunterhn »™fc,»n , f StS m the A^illos; and Professor Huxley, in his last 



aerfoZ LT Id le trl' 13 eXiSt ° nCe " **» ~ te > - *> t»e absence in that aLal of any 



resemblance in the sternal structure of those two groups 



W. K. Parker informs 



*-£-*-?- »™^° Anatomica. Fol H~ 8 ^T ^ 



This sesamoid can be seen very well in situ in +h» w+ * I . * P * 



h is t***™a ^ ^ *J?2 ' ' m the left fore foot of ^e skeleton of this somewhat rare Armadillo 



which is preserved in the British Museum. 



Hoyal 



specimens 



grand, renfle 



* This bone is described in the < Ossemens^ ,, ~ ™ 



m tres-inegale, * - * et se termini 2 £ £ 1 * ^ " " «" 

 sesamoid is represented by itself in figs. 12 and 3 ofT ' T ""* ^^ et " 



Rapp, in his already quoted mon graph upon tlv^T, "^ W ° rk ' 

 ** -d ist hier hinten a m diekstef 2 TJ^T^ "* ** *" - 

 halbmondfonnigen Knochen und dem Ospidforme" p 4' 



Th,s sesamoid can also be well seen in the fine skelet 

 d Brute contained in the Museum of the TW.i #vn_ 



The 



obern 



" besonders gross 

 zwei Gelenksflachen zur Artikulat 



fimired 



MS. 



