1880.] Mil. W. A. FORBES ON THE UAKARI MONKEYS. 633 



vertical. The perinseum measures about -35 of an inuli. The ischi- 

 atic jirominences, perinseum, and root of the tail are covered by- 

 greyish skill forming a rhomboidal space, about l-o inch broad and 

 high ; under the tail there is a slight hollow, with a raised fold of 

 skin at each side. 



The skin of the cheeks is thin and smooth throughout inside. 

 The hard palate has about ten slightly curved (lunate) ridges on each 

 side, best marked anteriorly, and not meeting mesially. The first 

 two lie between the canines, the last on the level of the last molar. 

 The more posterior ones are faint and irregular, and slraighter ; the 

 two most anterior the strongest and most curved. In front of the 

 most anterior are two small slits, one on each side of the centre, 

 directed antero-posteriorly, and lying in a line with the inner margin 

 of the median incisor. 



The tongue is elongate and parallel-sided, being bluntly squared 

 off at the tip. In front of the palato-glossal folds, which are well 

 developed, it is covered, above and on the sides, with filiform papillae ; 

 below it is smooth. The fungiform papillae are numerous, and dis- 

 tributed over the sides and tip of the tongue in front of the circuin- 

 vallate papillee ; of these there are four, arranged in the usual reversed 

 A-shape, the extra one lying on the right side. In Pithecia satanas 

 I found three only. There is a " INIayer's organ " of about 1 .5 slits, iu 

 the usual position in front of the palato-glossal folds. There is a 

 frcenum lingucc, and a smooth, fleshy-, well-developed subUngua, 

 bifid apicajly, with the duct of the submaxillary glands opening on 

 the two papillae behind this. The uvula is blunt and feebly developed. 

 All the salivary glands are well developed. The parotid is large, 

 measuring 2 inches across at its greatest development ; it occupies 

 part of the " anterior triangle," sending a lobe up and behind the 

 auditory meatus ; it then runs forward over the masseter muscle, the 

 superior border coinciding with the zygoma, as far as its anterior 

 bordei-, where on one side there is a small downwardly directed 

 lobule developed. Below it extends far into the fossa behind the 

 jaw, and is in contact beneath with the submaxillary. The duct 

 opens opposite the last premolar. 



The submaxillary glands are also large; in contact with the 

 parotids above, they nearly meet each other below. A few small 

 accessory lobules appear superficially towards the anterior part. 

 The glands are covered to a large extent by the jaw, running up on 

 the deep side of the ascending ramus of the mandible, and covering 

 there the digastric muscle ; at the angle of the jaw they appear super- 

 ficially. The sublingual glands, well developed, extend back in the 

 floor of the mouth for 1 inch behind the sublingua. 



On opening the abdomen, the great length and narrowness of the 

 abdominal cavity are striking. The caecum occupies superficially 

 nearly all the posterior part of the abdominal cavity, filling up thus 

 nearly one tliird of the whole. Behind, it rests on the bladder, covering 

 the rectum ; its apex, directed downwards, lies in the right iliac region. 

 The descending colon is quite superficial and lengthy, as is the 

 ascending, which is also superficial, except in the middle ; the trans- 

 Proc. Zool. Soc— 1880, No. XLII. 42 



