490 KIOHAHD EVANS. 



describing the species sumatranus Horst missed it, and 

 described the above-nieutioued opening found in the male as 

 the anus (fig. 5 and figs. 15 and 16). 



The Genital Orifice: — The genital opening in the 

 female is situated between the penultimate pair of legs 

 (fig. 5 and fig. 15), and has the form of a deep, transverse 

 slit, surrounded by tumid lips, which consist of whitish 

 papillte similar in characters to those which surround the 

 mouth. 



The genital opening of the niale of the species Horsti is 

 cross-shaped, the cross lines lying in the longitudinal and 

 transverse axes of the animal. The lobes situated in the 

 angles of the cross are made up of numerous papilla, which 

 are fused together to form four masses, on the top of which 

 occurs a small circular pit. The position of the male genital 

 orifice is between the penultimate pair of legs, as in the 

 female. The characters of the genital openings constitute 

 an unfailing external difference between the male and female 

 of the species Horsti (fig. 16). 



The Accessory Pore: — The opening of the male acces- 

 sory glands is situated between the last pair of legs. It is 

 triangular in shape, but its sides are slightly concave to- 

 wards the exterior. P;i,pilkB similar to those which sur- 

 round the male genital orifice form its boundary. Its 

 presence absolutely distiuguishes the male from the female 

 (fig. 16). 



The Number of Appendages: — The two specimens 

 belonging to the species Weldoni have]twenty-four pairs of 

 legs. The number of legs possessed by the young taken 

 from the uteri of these two specimens varies between twenty- 

 three and twenty-five pairs. 



Of the eleven specimens belonging to the species Horsti 

 two females have twenty-five pairs ; three females and one 

 male have twenty-four pairs, and five males have twenty- 

 three pairs. Out of five females two have twenty-five pairs, 

 and three twenty-four pairs ; while out of the six males only 

 one has as many as twenty-four pairs, the remaining five 



