ON THE I.EMURIDjE. 201 



The thumb of the hind hands in all the Lemurs (the Galeopithecus excepted) 

 is largely expanded at the tip, and furnished with a flat nail, while the index 

 has a pointed claw. In the Tarsier, however, as we have seen, not only the 

 index of the hinder hands, but the next finger also, is thus furnished ; and here 

 we trace a slight tendency to the exchange of nails altogether for claws, we see 

 that a step has been gained in the passage. We do not, indeed, by any means 

 intend to compare the hands of the Galeopithecus to those of the Tarsier, for in 

 the hinder hands of the former we cannot but recognize a decided resemblance to 

 the clinging feet of the Bat ; in this point, rather than in the possession of a 

 parachute, do we trace the marked affinity between Galeopithecus and Vespertilio. 

 The thin and slender tail of Galeopithecus, enclosed in a wide membrane to its 

 very tip (a membrane stretched between the posterior extremities), presents us with 

 another point of affinity. We find, then, that the head of Galeopithecus inclines to 

 the Lemurine ; the forehands neither those of a Bat or Lemur ; the hind-hands 

 and tail those of a Bat ; the membranous expansion (which extends from the 

 sides of the neck along the anterior extremities to the finger-ends, encloses the 

 fingers, stretches between the anterior and posterior limbs, and between the two 

 posterior limbs, enclosing the tail) differing from the wing of a Bat, inasmuch as 

 it is not constructed for flight, not developed anteriorly on slender fingers elon- 

 gated to sustain it, yet is it more developed, posteriorly, than the parachute of 

 the Flying Squirrels and Phalangers, in which the tail is free. 



So far, then, it would appear that the Galeopithecus takes an intermediate sta- 

 tion between the Lemuridce and Vespertilionidce, and it remains to be seen to 

 which of these two families it rather belongs. Let us examine the skull. 



In its general aspect it resembles that of a Lemur, but differs in many details ; 

 it is proportionably broader, shorter, and flatter ; the orbits are decidedly lateral, 

 with an elevated upper margin, the outer-ring being incomplete posteriorly ; in 

 the Lemur the ring of the orbits is complete, the intermaxillary bones scarcely 

 reach each other at their apex, and the incisor teeth, in pairs, are placed laterally, 

 with a wide intervening space. The zygomatic arch is very short and stout, the 

 extent of the temporal muscle is indicated by a decided ridge ; and the transverse 

 ridge of the occiput is remarkably prominent. The interorbital space, across the 

 upper part of the nasal bones, is far greater than in the skull of a Lemur of su- 

 perior size ; the auditory bullae are very small ; the outline of the palate repre- 

 sents about three parts of an oval, owing to the posterior molars on each side 

 being somewhat nearer to each other, than are those in the middle. The lower 

 jaw consists of two rami, the expanded base at the angle of each turning out- 

 wards. The coronoid processes are small conical elevations. 



Dentition. — Incisors above four, in pairs, placed laterally, with a wide inter- 

 vening space ; the first is small, compressed and pectinated ; the second is simi- 



