436 MR. A. H. G. DORA.N ON THE MORPHOLOGY 



cimens of Myogale examined by Byrtl, or if the stapedial intercmral artery was not, in 

 his examples, enclosed within the tympanum in a bony canal (whereas in the College 

 specimens that osseous tube nearly blocks up the whole aperture), it follows that there is 

 great variety among individual specimens in this respect, as I have actually observed in 

 the crania of Squirrels and Cavies. 



In the Mole (Talpa europcea, PI. LXII. fig. 5) the head of the malleus is rather large 

 for an ossicle of the laminated type ; it forms a distinct globular prominence above the 

 level of the articular surface, also projecting forwards. The area for articulation with 

 the incus is wide laterally on account of the head being hardly flattened at all in that 

 direction ; but it is not long vertically ; the facets form a sharp angle with one another, 

 and the uppermost is the larger. The neck is short and curved, the lamina wide 

 and rather opaque for so small a malleus ; the processus gracilis is thin and very fragile. 

 There is no orbicular process ; and the processus muscularis is reduced to a scarcely 

 perceptible tubercle. 



The manubrium is short, and forms an angle of about 120° with the neck. The outer 

 ano-le of the base, corresponding to the processus brevis, is considerably bent forwards ; 

 the whole manubrium is rather broad, laterally, at the base, but narrows rapidly, so as 

 to be almost styliform at the extremity. 



The incus of the Mole has an ill-developed body ; and the processus brevis is almost 

 obsolete. The processus longus is most characteristic, and has been long familiar to 

 comparative anatomists. It is deeply channelled out on its front and inner aspect, and 

 very long. It terminates in a proportionally small, pedunculated Sylvian apophysis. 



The stapes is similar in form to that of Myogale ; the crura are very slender and well 

 arched. The intercrural canal is very small, and justifies Hyrtl's remark quoted in the 

 above description of the Daesman's stapes. 



The extreme difference between all the ossicles of this animal and those of the Golden 

 Mole ( Ohrysochloris) is most instructive and significant ; the great distinctions between 

 the malleus of Talpa and that of Condylura, where the incus is very similar, are also 

 interesting, but less to be expected. 



The malleus of Scalops has a large head, as in the last genus ; its lamina too is of the 

 same form. There is a small tubercular processus muscularis close to the root of the 

 manubrium, which latter fragile process is very readily broken in examining the attach- 

 ment of the tensor muscle of the tympanum in the recent skull. 



The incus (PI. LXII. fig. 6) is more generalized than in either Talpa or Condylura, as 

 the processus brevis is not so rudimentary ; and though the stapedial crus is long, it is 

 not so remarkably broad as in those animals. As in them, however, it is deeply 

 channelled. 



The malleus of Condylura (PI. LXII. figs. 7, 8) is doubly interesting :— first, because 

 it is so different from that of Talpa ; secondly, because it possesses, like Myogale, a pro- 

 cessus muscularis remarkably like the orbicular apophysis seen in the Shrew. 



The head of the malleus in the Star-nosed Mole is very small ; nor is the articular 

 surface deep vertically ; its upper facet is wider than the lower. The neck is very long 

 and narrow, and is bent into a very sharply projecting angle midway between the head 



