NOTES ON THE PEKIPATUS OF DOMINICA. 289 



Apertures. — The anus is situated posteriorly between the 

 legs of the last pair. 



The generative aperture in both sexes is found ventrally 

 between the legs of the penultimate pair. 



The segmental organs of most of the appendages open into 

 the foot-groove close to the junction of the leg with the body. 

 On the fourth and fifth pairs, however, the aperture is situated 

 on a papilla between the proximal and third foot-pads (fig. 5). 



Internal Anatomy. — Male Generative Organs (fig. 6). 

 — The vas deferens of each side is extremely short. Each 

 passes under the nerve-cord of its own side, and the two then 

 unite to form a very long coiled ductus ejaculatorius. 



A pair of accessory glands are present, but these are much 

 shorter than those of the other South American forms which 

 have been described. 



The accessory glands open out independently on either side 

 of the anus, as in P. Edwardsii, not into the ductus ejacula- 

 torius, as described for P. capensis. 



In figs, 10 a — c, three sections through the testis are figured. 

 Of these the most anterior ffig. 10 a) is through the prostate 

 {pr. in fig. 6), and shows simply a mass of large nuclei sur- 

 rounded by a single layer of flattened epithelial cells. The 

 layer of epithelium round the nuclei of the prostate is a point 

 to be noticed, since Gaffron (2), in his description of P. 

 Edwardsii, states that there is in this region no epithelial 

 covering to the cells, which are simply enclosed in a thin 

 muscular sac. Gaffron, in fact, makes this a distinction 

 between the prostate (Schlauchhoden) and the testis proper 

 (Blasenhoden). This is well seen in his figure (Taf. xxiii, fig. 

 46), and is clearly described in his own words : — " Der bedeut- 

 samste Unterschied zwischen Schlauch und Blasenhoden ist 

 jedoch das Vorhandensein eines characteristichen Epithels im 

 letzterem. Wahrend der diinnhautige Sack des Schlauch- 

 hodens gleichmassig und dicht angefiillt ist mit grosseu Zellen, 

 die sich nicht zu einem geschlossenen Wandungsepithel anord- 

 nen, liegt der eben beschriebenen Blasenhodenmuscularis 

 innen ein sehr regelmassiges polygonales Pflasterepithel.^' 



