,64 



by my-self in an earlier paper and drawn up after a single, badly 

 preserved specimen, collected by von Horstock at the Cape of Good 

 Hope. I believe, that the specimen from Java, described by Rosa as 

 P. operculata a ) , must also be referred to this species , for it agrees 

 with our specimens in its main characters , specially in the peculiar 

 appearance of the spermathecae. 



13. Perichaeta Houlleti Perrier. 

 (— campanulata Rosa). 

 Sumatra: Singkarah, six specimens. 



The longest example measures 200 mm. in length. The appearance 

 of this species is not so slender as that of P. indica. 



The circle of bristles is noticeable by its white colour. The clitellum 

 shows no setae nor intersegmental grooves to the naked eye. There 

 are 50 à 52 setae in the segments immediately behind the clitellum; 

 they are arranged in a continuous row. Upon segment XVIII, in the 

 space between the male generative pores , 12 setae are to be seen. Those of 

 the clitellum have a bifid extremity and the rudimentary appearance, 

 first observed by Beddard 2 ) and confirmed by Bourne 3 ). It is 

 proved by this fact, that Bourne's suggestion 4 ), „that all the species 

 of one genus should behave in the same way" with regard to the 

 presence or absence of setae is entirely erroneous; for in adult spe- 

 cimens of P. indica, I never observed bristles upon the clitellum, 

 while on the contrary in P. affinis they are present. I therefore quite 

 agree with Beddard, that this is a characteristic of a given species, 

 that should be carefully noted 5 ) ; for it is difficult enough to discri- 

 minate the numerous species of Perichaeta. I will not deny that in 

 young examples of P. indica setae probably are also present on the 

 clitellar segments, but this it no impediment for making use of their 

 total absence in the adult worm in our .diagnosis. Though lion's whelps 

 have a spotted skin as most felidae , the adult animal is characterized 

 by the absence of spots. 



The cephalic lobe extends over half the buccal segment; the 

 first dorsal pore lies in the intersegmental groove XI/XII. 



1) Ann. K. K. Naturh. Hofmuseums , Bd. VI, 1891, p. 398, pi. XIV, figs. 6 and 6bis. 



2) Proc. Zool. Society, 1887, p. 389. 



3) Journ. Asiat. Soc. of Bengal, T. LVIII, 1889, p. 110. 



4) Quartl. Journ. Micr. Science, T. XXXII, 1891, p. 54. 



5) Proc. Zool. Soc, 1890, p. 64. 



