AMPHIBIANS. 69 



helps to form the glenoid cup fully as much as the scapula. A massive bone above, the pne- 

 coracoid gradually narrows to a point, and is, on the whole, a long falciform bar, with its convex 

 margin behind, and ending below in a jagged, thin, partially ossified cartilage, which lies in 

 apposition to its fellow of the opposite side (Plate VI, figs. 10 and 12.) Both in this bone and 

 the coracoid (cr.) the Dactylethra curiously adumbrates those Toads-in-armour (Schildkroten) the 

 Tortoises ; for the coracoid is also a long and delicate rod, scarcely distinguishable from that of 

 the young Green Turtle (Chelone my das, see Plate XII, fig. 2, cr.) ; and having a similar lunate 

 cartilaginous epicoracoid (e. cr.). This piece which has in it a small endosteal patch, runs along 

 by its fellow for some distance ; but, as far as Hyrtl's beautiful preparation shows, ends in a point 

 a long distance from the prse-coracoid flaps (fig. 10, p. cr. and c. cr.). 



The Sternum (st.) is shaped like a rose-petal, the narrowed part lying between the epicoracoids : 

 like the Shoulder-plates it is abnormal, being unossified, as in the Urodela. 



A 4. Supra-scapula scarcely larger than in Microps ; scapula uncleft, and of great length ; 

 prae-coracoid and coracoid extremely unequal. 



Example 1. Systoma gibbositm, Wagler. 



Plate VII, fig. 9, shows the Shoulder-girdle and Sternum of an old male of this species 

 (from the Cape of Good Hope), seen from an antero-superior aspect, and magnified four diameters : 

 it is a most abnormal type. 



The supra-scapula (s. sc.) of this species is narrow, somewhat lunate, rounded above, mar- 

 gined by endosteal cartilage, which appears most in the notch at the base of the bony sheath ; 

 it is set on to the scapula at a right angle. The scapula (sc.) is more like that of a Cheloniau 

 than an Anouran, being an almost cylindrical rod, and passing by anchylosis at once into the 

 prse-coracoid and coracoid (p. cr., and cr.). These bars are reversed as to relative size ; for the 

 coracoid is, as a rule, the largest ; here, however, it is extremely small, whilst the prae-coracoid is 

 of great breadth, especially where it meets its fellow : there is but little epicoracoid margin (e. cr.) 

 to these bars. This curious Shoulder-girdle is almost precisely like the Hip-girdle of certain 

 Chelonians, e.g. Caretta caouana. Small as is the epicoracoid band, yet the left overlies the 

 right, and the narrow end of the oval " coracoid fenestra" (c. f.) is towards this band. The Sternum 

 (st.) is oval, very small, and endosteally ossified ; it is by far the smallest Sternum I have met 

 with. 



I 



Example 2. Systoma granosum, Dumeril. 



Plate VII, fig. 10, shows the postero-superior view of the Shoulder-girdle of an adult 

 female of this species (from the Cape of Good Hope), magnified three diameters. This in many 

 respects differs but little from that of 8. gibbosum ; the supra-scapula (s. sc.) is more pointed and 

 straighter ; the scapula (sc.) is shorter and stouter, and ends in front in a kind of projection 

 quite similar to what I have described as the " preacetabular spur" in the pelvis of Gallinaceous 

 Birds ('Trans. Zool. Soc.,' 1864, vol. v, part 3, p. 166). 



The three bones, scapula, coracoid, and prae-coracoid, are not anchylosed together, and the 

 two latter have entirely reversed their relative proportions ; the coracoid (cr.), is now a very 



