194 



COMPARATIVE ANATOMY. 



A well-differentiated Harderian gland is present in the whole 

 series of animals from the tailless Amphibia to the Mammalia. 

 Amongst the latter it is wanting in the Cetacea and Primates only. 



Tit 



FIG. 159. DIAGRAM OF THE LACRYMAL APPARATUS or MAN. 



TJ), lacrymal gland, divided up into several portions ; **, ducts of the lacrymal 

 gland ; ft, puncta lacrymalia ; TR, TR 1 , upper and lower lacrymal canals ; 

 >y, lacrymal sac ; D, naso-lacrymal duct. 



The Meibornian glands, belonging to the group of sebaceous 

 glands, are confined to the Mammalia, and lie embedded in the 

 substance of the eyelids in the form of branched tree-like tubes 

 or clustered masses. They open on the free edge of the lid, and 

 produce a fatty secretion. 



BIBLIOGRAPHY. 



BERGER, E. Beitrdge zur Anatomie des Sehorgancs der Fische. Morphol. Jahrb. Bd. 



Y1JL 1882. 

 BOLL, F. Zur Anatomie und Physiologic, der Retina. Arch. f. Anat. u. Physiol. 



1877, Physiol. Abthl. 



CARRIERE, J. Die Sehorgane der Thiere. Miinchen und Leipzig, 1885. 

 HEINEMANN, C. Beitrdge zur Anatomie der Retina. Areh.f. mikr. Anat. Bd. XIV. 



1877. 



KESSLER, L. Zur Entwicklung des Auges. Leipzig, 1877. 

 LEUCKART, K. Organologie des Auges. In A. Grae/e und Th. Saemisch, Handbuch 



der gesammten Augenheilkunde. Bd. I. Anatomie und Physiologic. 

 MANZ, W. Entw.-Gesch. des menschl. Auges. Ibid. 

 MULLER, H. Gesammelte und hinterlassene Schriften zur Anatomie und Physiologic 



des Auges. Herausgegeb. von 0. Becker. Leipzig, 1872. 

 MULLER, W. Ueb. die Stammcscntwick. des Schoryanes der Wirbelthiere. Festgabe 



von C. Ludwig. Leipzig, 1874. 

 SARDEMANN, E. 'Die Thracnendrilse. Preisschr. Frieburg i/B, 1884. Abstract in the 



Zool. Anz. 1884. 

 SCHULZE, M. Die Retina. Strieker's Handbuch der Lehre von den Geweben. 



Leipzig, 1871. See alsD Archiv fur mikr. Anatomic, Bd. II., 111., lA r ., \., 



VI., & VII. 

 SCHWALBE, G. Lchrb. d. Anatomie der Sinnesorganc. Erlangen, 1883. 



AUDITORY ORGAN. 



It is very probable that the auditory organ, like those of 

 smell and taste, has been derived primitively from a modified 

 integumentary sense-organ (organ of the lateral line). The 



