444 MR. A. H. G. DORAN ON THE MORPHOLOGY 



is of a type hardly seen except in certain Oebidse and Lemuridse ; the stapes has no par- 

 ticularly high affinities. In the malleus G-aleopithecus is decidedlv allied to the Macro- 

 scelidse among Insectivora, and to no other family in this Order ; but in the incus it more 

 approaches Tupaia. 



IV. In the Tupaiidse the malleus assumes to an extreme degree the neckless and non- 

 laminated type common in most Cebidae and some Lemurs, as well as in Sciurus ; but the 

 manubrium is rather of the form prevailing in the above-named Primates than of that 

 seen in the Squirrels ; and so in every respect is the incus. All the ossicula differ from 

 the varied forms in other families of the Insectivora, except that the incus somewhat 

 approaches in type that of Galeopitheeus. Taken as a whole, the ear-bones of Tupaia are 

 higher in type than in any other family belonging to this Order. 



V. The Macroscelidse have a more specialized malleus than can be seen in any other 

 insectivore except Chrysochloris ; the extremely constricted neck and the narrow lamina 

 and processus gracilis running straight forwards to the Glaserian fissure are highly 

 characteristic. The processus muscularis is well-developed. The head is better-deve- 

 loped in Rhynchocyon than in Macroscelides. In Petrodromus the malleus is far more 

 like that of Sorex than in the two former genera ; but the incus is not in any sense 

 Shrew-like. 



VI. In the Shrews, the Myogalidse, Talpidse, Centetidae, and Hedgehogs proper one 

 common feature exists — a malleus with a wide lamina and a processus gracilis united to 

 the tympanic ring after the fashion of the Marsupials — in short, a low type of malleus. 

 The processus brevis of the incus is always ill-developed except in the Centetidse and 

 Gywmura. The intercrural aperture of the stapes is always wide. 



VII. In the Soricidse the malleus has a moderately wide lamina, an orbicular apo- 

 physis, and a more or less distinct processus muscularis, to which, and not to the 

 spherical protuberance, the tendon of the tensor tympani is inserted. As a whole the 

 malleus is very much like that of a Marsupial. The stapedial crus of the incus is not 

 very broad. 



VIII. In the Myogalida3 the malleus differs in several respects from that of the Shrews 

 proper : the manubrium is of stouter make ; and an orbicular process exists, which pro- 

 bably is the homologue of that in the malleus of Sorex, but certainly functionally 

 replaces the processus muscularis, absent in Myogale. The incus resembles that 

 of Sorex. 



IX. In the Talpidae the malleus of Condylura most resembles that of Sorex, but has an 

 orbicular process serving as a processus muscularis, as in Myogale ; its incus resembles 

 that of Talpa. In Scalops the incus has not the chief distinguishing feature seen in 

 Talpa and Condylura ; but its malleus is of the form seen in the common Mole, where 

 the head is better-developed than in the Shrews and Hedgehogs, and the lamina not so 

 broad. The incus of Talpa has a very broad and channelled processus longus. 



X. The Erinaceidse and Centetidse have a more specialized malleus than the Shrews, 

 Daesmans, and Moles. The great feature is the very broad processus gracilis perforated 

 to transmit the chorda tympani nerve ; the processus muscularis and an ill-developed 

 orbicular process coexist ; the lamina is very broad. In Centetes and JEriculus the pro- 



