236 LEMURS. 



Extinct Lemuks. 



We have already incidental!}- referred to the occurrence of several fossil 

 lemurs in the lower Tertiary strata of Europe : but it remains to be mentioned tliat 

 other species have been found in the corresponding rocks of North America. This 

 is a very curious and highh' important cii'cumstance, since it suggests that while the 

 New World monkeys and marmosets, which have very lemur-like molar teeth, maj- 

 have taken their origin directly from the extinct lemurs of that hemisphere, the Old 

 Woi'ld monkeys may have had an independent origin from the ancient lemurs of 

 Europe. 



Curiously enough, although the remains of lenuirs have been known for very 

 many years from the lower Tertiary rocks, both of Hampshire and France, it is 

 only quite recentl}' that they have been recf>gnised as such, hav-ng been long 

 regarded as belonging to small hoofed mannnals. One of these groups of lenmrs, 

 represented by several species of different, though relatively small, dimensions, 

 occurring both in England and France, has been described under the name of 

 Microchoerus ; the tei-m meaning " small pig," and having been applied from the 

 supposed aflSnity of the creature to the hoofed mammals. These animals were 

 undoubtedly lemurs nearly allied to living forms, their skulls being very like those 

 of tlie galagos, although their upper premolar teeth more nearly resembled those 

 of the mouse-lemurs. Like all other fossil lenuirs, they are, however, distinguished 

 from living forms by the circumstance that the place and form of the loM'er tusk 

 is not taken b}- the first of the lower premolar teeth (see p. 203). This is a very 

 important circumstance, since it shows that tliese ancient lemurs were what zoologists 

 call less specialised than their living relations, and also removes any difficulty as 

 to the descent of monkeys (in which the lower tusk always I'emains) from lemurs. 



Another and larger European Tertiary lemur, known as the Adapis, carries 

 the series one step still further back, since it has four premolar teeth on either side 

 of each jaw ; whereas, as we have seen, no living lemur has more than three of 

 these teeth. Here, then, so far as it goes, we have decisive evidence of the 



approximation of the extinct lemurs to the inferior 

 onlers of IMamnials, among which four premolar teeth 

 are freijuently present : and we may thus hope in time 

 to discover further evidence of intermediate forms. 



.Some of the extinct North American leuuirs, 

 with four premolars, do indeed exhibit certain tran- 

 THB LEKT UPPER CHEEK-TEETH OP AN sitloual cliaractcrs ; but it would be beyond the 

 EXTINCT EUROPEAN LEMURoiD pi-Qyincc of tlio prcseut work to cntcr uiion their 



(Adapis). V • 



discussion. 

 There have recenth' been discovered in the superficial deposits of Madagascar 

 the remains of a gigantic extinct lemur, described under the name of Megalada2}is. 

 The skull presents some resemblance to that of Adapis: l>ut the upper molar teeth 

 are triangular. Like many of the foregoing this lemur indicates a family by itself. 

 Not improbabl}^ it was living about two centuries ago. 



