118 MR. E. H. BURNE ON [Feb. 19, 



of the two lobes into which the gland is divisible. After a short 

 course free of the gland-substance, the ducts are said to open into 

 a spindle-shaped muscular reservoir, from the anterior extremity 

 of which a single duct (Wharton's duct) leads to an opening in 

 the floor of the mouth beneath the tongue. This description 

 is only partially true, for, of the two main collecting-ducts, one 

 only (i. e. that coming from the larger and most posteriorly situated 

 lobe of the gland) opens into the muscular reservoir and continues 

 from its anterior extremity to the opening beneath the tongue ; 

 the other, although it enters the \\all of the reservoir, has no com- 

 munication with its cavity, but courses down its dorsal margin 

 close beneath the lining epithelium and continues as a separate 

 duct, intimately connected with the first, to an opening beneath 

 the tongue. (It was not seen whether these two ducts opened 

 iuto the mouth by a common aperture or separately.) 



An arrangement of the submaxillary gland and ducts precisely 

 similar to this was found in Dasyjms sexcinctus (text-fig. IS), but, 

 owing to the greater size of the creature, the individuality of the 

 ducts was more easily seen. Somewhat similar features were also 

 observed in the Three-toed ^\oihL{Bradypus ^v/t/aci^^y/its, text-fig. 19). 

 The submaxillary gland in this animal is divisible, as in the above- 

 mentioned Dasypodidse, into two well-marked lobes each provided 

 with its own duct. The two ducts run side by side (with, however, 

 no muscular reservoir on either of them) to the floor of the 

 mouth beneath the tongue. The duct from the smaller and more 

 anteriorly situated lobe of the gland is remarkable for its large 

 calibre and for the thinness of its walls — in fact at first sight it 

 had very much the appearance of a vein. The duct from the 

 larger and posterior lobe was double throughout its length on the 

 right side, but single on the left. The meaning of the conditions 

 observed in the submaxillary glands and ducts of these three 

 Edentates becomes, I think, c-lear on reference to a paper by 

 Eanvier\ in which, in addition to nunaerous observations of his 

 own, he collects and harmonizes the previously confused statements 

 concerning the relations that subsist between the sublingual and 

 submaxillary glands. It is well known that frequently in Man 

 there occurs a large duct (duct of Bartholini) that arises from a 

 posterior portion of the sublingual gland and runs alongside Whar- 

 ton's duct to open with it or near it under the tongue. Bartholini 

 himself ^ described and figured a similar duct in the Lioness, having 

 its gland in close connection with the submaxillary, and Eauvier 

 adds a large number of mammals in which the same gland (called 

 by him Eetro-lingual) is found with great constancy. According 

 to Eanvier the retro-lingual gland Hes always posterior to the 

 lingual nerve, and for this reason (a somewhat arbitrary one it 



1 Eanvier : " Etudes anafcomiques des Glandes connues sous les noms de sous- 

 maxillaire et sublinguale, chez les Mammiferes." Arch, de Physiol, xviii. 1886, 



^Bartholini : De ductu salivali hactenus non descripto observatio anatomica, 

 1685. 



