KUNGL. SV. VET. AKADEMIBNS HANDLINGAR. BAND 49. N:0 7. 29 



series of closely set small papillae forming an edge along the anterior side of each 

 fold, but separated from the same. There are also scattered papillae elsewhere in the 

 palate. Eleven folds in all can be discerned. The first in front of the canines is 

 least developed. The following five are arcuate but with the forward directed convexity 

 gradually lessened. These five folds run respectively between the canines and the 

 premolars (p^ to p*). The next three folds have a tendency to be interrupted in the 

 median line and thus form pairs of arcuate folds. The tenth fold consists of two 

 short transverse folds opposite to m^ The eleventh fold is continuous but also straight 

 and transverse and situated opposite the interspace between m^ and m^ Behind the 

 last fold there are numerous small papillae scattered on the palatal surface. Such 

 papillae are thus very numerous in this species which perhaps stands in connection 

 with its to great extent insectivorous diet. 



The male organ of Rhinoceros bicornis. 



Among the Artiodactyla the very variable shape of the male organ can be traced 

 back to a common type from which all the numerous modifications^ can be derived 

 by reduction of different portions, or some other alterations. It appears a little more 

 difficult to decide whether a common type may be found from which the male organ 

 of all the recent Perissodactyla may be derived. When reviewing our present know- 

 ledge about this organ among the vertebrates, especially the Amniota Gbrhardt^ 

 points out as common characteristics to the male organs of all Perissodactyla: »Be- 

 deutende Lange und Dicke des ganzen Organs, starke Entwicklung der Glans und 

 Fehlen eines Septums samt Penisknochen. » The last two characteristics are negative 

 and shared by others as well. 



Of the three families of Perissodactyla which have survived to the present time 

 it is in the first rank Rhinocerotidce which will be considered at this opportunity. 

 The genus Rhinoceros of the present time has been divided in three subgenera viz. 

 Dicerorhinus, Diceros and Rhinoceros s. str. The male organ of a member of the 

 first and last of these subgenera has been described and figured before. That of 

 Diceros bicornis is to be described below, and its appearance is shown on PI. II, Fig. 3 

 (dorsal view) and Fig. 4 (lateral view). Owen described the male organ of Rhino- 

 ceros unicornis already 1852.^ He drew attention to the peculiar fact that »the apex 

 is not simple, but resembles a mushroom on a thick peduncle projecting from an 

 excavation at the end of the glans with a thin wall or border, like a second pre- 

 puce* — — — ; and further that »on each side of the base of the glans, and rather 

 towards its under ^ part, there is a longitudinal ridge or lobe three inches and a half 

 in length and eight lines in basal thickness* — — — . 



^ The Tylopoda might, however, form an exception, but I do not know their male organ from my own 

 experience. 



* Ergebnisse u. Fortschr. d. Zqologie. Bd. 1. Hft. 2. Jena 1908. 



^ Trans. Zool. Soc. London. Vol. IV. Part 2. PI. 9. This description is also repeated with more 

 details in Owen's »Anatomy of Vertebrates* III, p. 663 & 664. 



* ought to be » upper »! 



