374 



NATURAL SCIENCE. ■ December. 



Rosenberg (187a), Lazarus (153), Kohlbriigge (313), and Deniker (17) ; 

 regarding the vertebral column, Cunningham (118) and Kohlbriigge 

 (313); for the sacrum, Broca (104) and Paterson (179) ; as to the 

 sternum and ribs, Ruge (316) and Keith (149). 



The Teeth. — The general characters of the teeth have been 

 described by Owen, Huxley, and Tomes, and more mmutely by 

 Topinard (82), Magitot (56, 57), and Giebel (240, 305) ; Kohlbrugge 

 (313) and Duvernoy (22) have also made passing observations con- 

 cerning them. Bateson (92) and Lessona (314) have dealt with the 

 anomalies of the dental series. No one, with perhaps the exception 

 of Giebel, has worked out in any detail the dental characters of the 

 species ; but, speaking from my own experience, only the teeth of 

 H. syndactylus present features at all distinctive, but, as I had occasion 

 to remark when dealing with the skull, the material to which I had 

 access was too small to allow of a positive statement being made. 



The Alimentary System. — The alimentary tract has been 

 examined from end to end by Deniker (17) and Kohlbrugge (313). 

 Smaller and more general communications have been made by 

 Bennet (292), BischofF (293), Flower (28), Hunter (310), Yarrel (329), 

 and Keith (31 1«). All, with the exception of the two last-named, 

 have given descriptions of the liver. 



The Respiratory System.— Deniker (17) and Kohlbrugge (313) 

 give full descriptions of this system. Only the Siamang possesses air- 

 sacs prolonged from the ventricles of the larynx — see Sandifort (271), 

 Bennet (292), and Kohlbriigge (313). The last-named and Eschricht 

 (299) give full descriptions of the muscles of the larynx. Some 

 details concerning this system may be obtained from the writings of 

 Bischoff (293), Hunter (310), Sandifort (271), and Duvernoy (22). 

 Ruge (189) has investigated the relationships of the pleural and 

 pericardial cavities to the chest-wall. 



The Circulatory System. — It is much to be regretted that only 

 very incomplete descriptions of the arterial and venous systems have 

 been pubhshed. Deniker's (17) is the best, but a good deal may be 

 learned from the accounts of BischofF (293), Kohlbriigge (313), and 

 Hunter (310). Keith ,(147, 311) has pointed out the arrangement 

 of the trunks of the aortic arch and abnormalities of the inferior vena 

 cava. The dimensions of red blood-corpuscles are given by Gulliver 

 (135), and the position of the heart by Ruge (189). 



The Ductless Glands. — The thyroid, thymus, and spleen are 

 described by Deniker (17), and Kohlbrugge (313). Keith (311^) 

 observed that the spleen did not become enlarged even in gibbons 

 inhabiting very malarious districts. 



The Genito-Urinary System. — Harlan (307) described a speci- 

 men which, according to him, was one of those extreme mammalian 

 rarities, a true hermaphrodite possessing both ovaries and testicles. 

 No microscopic examination of these organs was made, the testicles 

 having been taken away in the removal of the skin. The greater part 



