78 SHOULDER-GIRDLE AND BREAST-BONE. 



and highly developed, although in this young specimen the azygous, terminal cartilages are 

 yet soft. " Ectostosis " is more potent in this species than in any other I have examined ; not 

 excepting even the Systoma : it resembles, in this respect, the Carp amongst Osseous Pishes ; 

 whilst Pelobates reminds one of the Lump-fish (Cyclopterus lumpus), 



The "omosternmu " (o. st.) is not very much shorter than the true Sternum (st.) ; but it is 

 much slenderer ; its free anterior cartilage is rounded, rather broad, and much like the free, 

 rounded xiphisternum (x. st.). The scapula breaks into a glenoidal and a prse-scapular fork 

 (p. sc., sc. f., sc.) ; and the prae-coracoid (p. cr.) is of the normal form, but very long and slender, 

 and it is separated from the coracoid (cr.) by so long and pointed a fenestra (cr. f.) that it very 

 nearly forms a notch, as in the Turtles, and in Struthio camelws. Moreover, its inner and outer 

 laminae have met behind, and the only uncovered cartilage is the small connection between it and 

 the coracoid. This latter bone is of the normal phalangoid shape ; but, having taken up nearly 

 all the basal region by ectostosis, it is very broad and pedate sub-mesially, and approaches that 

 of the Bird, when there is no distinction, in ostosis, between the coracoid and the epicoracoid. 

 The junction of the two coracoids at the mid-line is sinuous ; there is a very scant quantity of 

 cartilage at their edges. 



Example 4. Megalophrys montana, Kuhl. 



Plate VII, fig. 8, shows the Shoulder-girdle of this kind magnified four diameters ; it was a 

 young male from Java. The supra-scapula (s. sc.) is more regularly square than is usual, and 

 the outer bony part is more deficient behind ; yet the endosteal bone is nearly coextensive 

 with the cartilage. The scapula (sc.) is very broad, and the fenestra (sc. f.) cleaving it below is 

 very small ; the base of .the forks is very extended, so that the heads of the prse-coracoid (p. cr.) 

 and coracoid (cr.) are broad also. The prae-coracoid is serpent-fang-shaped, and much extended 

 forwards ; the coracoid is very stout and short, is more than usually turned backwards : thus the 

 coracoid fenestra (cr. f.) is short and broad. The epicoracoid band (e. cr.) endosteally ossified, 

 and narrowest at the middle, is much extended fore and aft ; and the left, normally, overlaps the 

 right. The omosternum (o. st.) is very small, oval, and unossified ; but the true Sternum (st.) is 

 almost twice the average length ; has a small amount of soft cartilage at each end ; the anterior, 

 prae-sternal end is angular ; the xiphoid end (x. st.) is but little extended, either laterally or 

 axially, beyond the shaft-bone. This is a long, flat, narrow-waisted bar, long enough to be made 

 into the many segments of the mammalian Sternum. 



Example 5. Rana alpina, Laurenti. 



This Austrian species is perfectly typical in its Shoulder-girdle ; and both the Shoulder- 

 sternum and the Sternum proper have a shaft and an epiphysis. My preparation of Rana tem- 

 poraria does not show any internal bone in the broad end of the " omosternum ;" this may be 

 merely a matter of age. I shall not give figures of either R. alpina or from my own specimens 

 of R. esculenta, but finish this group by describing the development of the common species. 



