498 MISS JOAN B. PROCTER ON THE 



under the first is entire ; those beneath the second and third 

 divided mesially by a narrow transverse bridge of bone formed by 

 the third and fifth costal plates. There is no large fenestra 

 beneath the fourth in the normal adult, 



Nuchal plate moderate, posterior corner free, forming anterior 

 edge of first median fenestra, which exposes the ninth vertebra. 



First neural plate (text-fig. 8, np. 1) very much reduced in 

 comparison with that of a normal Testudo ; anterior edge pointed, 

 bordering first fenestra by which it is separated from the nuchal 

 plate ; narrow lateral limbs, uniting by short sutures with first 

 pair of costal plates {pp. 1) ; narrow posterior limb, entering into 

 second median fenestra, where it forms part of the dividing 

 bridge and unites by short suture with the second neural. 



Second neural plate {ni). 2) vestigial, barely wider than the 

 vertebrae beneath, with straight lateral edges, ixniting by short 

 sutures with preceding and succeeding neurals, and forming the 

 main part of the fenestra) bridge. 



Third neural plate {np. 3) octagonal, very much reduced, oblique 

 edges free, curved invertedly, bordering the inner corners of the 

 second and third fenestrse, which this plate divides one from the 

 other by uniting with the second costal plates {pp. 2) by narrow 

 sutures, thus forming a narrow bridge between them ; also form- 

 ing similar connections with second and fourth neurals. 



Fourth neural plate {nj). 4) similar to second but somewhat 

 broader in proportion, forming the longitudinal dividing bridge 

 across the third median fenestra. 



Fifth neural plate {np. 5) precisely similar to the third. 



Sixth neural plate {^np. 6) similar to second and fourth but 

 broader still, dividing fourth median fenestra, which is, however, 

 much smaller than the two preceding. 



Seventh neural plate (??/>. 7) normal, hexagonal, without free 

 edges, uniting by six sutures with the sixth and eighth neural, 

 and seventh and eighth costal plates respectively; those formed 

 with the eighth costals slightly longer than the others. 



Eighth neural plate {^np. 8) normal, sub-tetragonal, without free 

 edges, uniting by oblique sutures with the eighth costal, and by 

 transverse ones with the seventh neural and first pygal plates, 

 the latter suture the longer and curved. 



First pygal plate broadly cordiform or septagonal, set almost 

 at right angles to the horizontal plane of the neurals, curving in 

 where the marginal epidermal shields meet the fifth vertebral, 

 and curving out more obliquely to form a point beneath the supra- 

 caudal shields. It forms sutures with the eighth neural and 

 costal, eleventh marginal (7??^. 11), and second pygal {p. 2) plates, 

 that with the eighth neural about twice as long as any of the 

 others and curved invertedly. 



Second pygal normal, equal in size to the eleventh marginal 

 plate. 



First costal plates {cp. 1) shaped like wings, uniting by short 

 sutures with the lateral edges of first neural (which forms a 



