520 Opposable power of the Thumbs 



natural group of Pedimana, I would remark, in the next place, 

 that these animals, particularly those which possess the pre- 

 hensile power of the tail, are remarkably slow, awkward, and 

 undecided in their movements, advancing only with great 

 caution and deliberation, as if not perfectly confident of their 

 powers of prehension. This character is equally remarkable 

 in the other prehensile-tailed mammals, in the Synetheres, 

 Myrmecophaga, and Cercoleptes, which exhibit the same un- 

 steady wavering gait, and the same slow awkward move- 

 ments. All are, moreover, distinguished by their timidity, 

 gentleness, and docility; results which naturally follow from 

 their want of confidence in their own powers. More active 

 and favourably organised mammals, which have a freer use of 

 their limbs, and do not require at every step to secure their 

 tottering equilibrium by the slow and awkward operation of 

 twisting the tail round whatever object happens to be within 

 reach, display a corresponding quick and petulant tempera- 

 ment, because they are equally aware of their power to avoid 

 or retaliate the assaults of their enemies ; but the prehensile- 

 tailed animal must be content to trust to cunning and sagacity 

 to elude attack, or surprise its less wary prey. In this respect, 

 also, there is a notable difference between the characters of 

 the Pedimana and Quadrumana. Among the latter, the Loris 

 (Nycticebi) alone resemble the Pedimana in their tardy pace 

 and insecure movements ; whilst among these the nearest ap- 

 proximation to the lively, petulant, and capricious temper of 

 the Simiae and Lemuridae is made by the Cebi and Callitrices, 

 the very genera which, as I have already observed, approach 

 them most nearly in organic conformation. 



A farther, and not less interesting, relation of affinity, which 

 subsists between the two minor groups of the Quadrumana and 

 Pedimana respectively, regards the geographical distribution 

 of these animals ; the former being exclusively confined to the 

 Old World, and the latter almost as exclusively to the New ; 

 the only exception being in the case of a single genus of Didel- 

 phidous Pedimana (Phalangista), some species of which are 

 spread over that long chain of islands which unite the south- 

 eastern shores of Asia with the north-eastern coast of Australia, 

 and which are partly considered to belong to each of these 

 continents. The intermediate position of this locality, how- 

 ever, between the two proper and chief habitats of the Qua- 

 drumana and Pedimana respectively, can scarcely be considered 

 as an exception to the general law of geographical distribution 

 just announced, since it is a necessary and well-known fact 

 in the dispersion of animals and vegetables, that the appro- 

 priate productions of conterminous climes are more or less 



