new African Earthworm. 451 



Dichogaster jaculatrix, sp. n.* 



External Features. 



The specimens vary in length between 18 and 34 cm., and 

 have a diameter of about 10 mm. The number of segments 

 is about 180. 



The colour during life, according to Dr. Christy, was a 

 "greenish blue." The cuticle of the specimens in spirit still 

 shows a beautiful green and blue iridescence, the colours 

 being remarkably intense and brilliant. Beneath the cuticle 

 each segment is marked, on the dorsal side, with a purplish 

 transverse band. 



The prostomium is small, entering into a slight notch in 

 the anterior border of the first segment. Often, however, it 

 is completely withdrawn into the buccal cavity. 



The clitellum commences on segment xiii., and extends 

 back to segment xxii. or xxiii. The "genital area" on the 

 ventral side of the clitellar region is roughly hourglass- 

 shaped in outline, and usually rather deeply sunk. It 

 occupies segments xvii.-xix. The pores of the spermiducal 

 (" prostate") glands are arranged in two pairs, a pair near 

 either end of the genital depression, on segments xvii. and 

 xix. respectively, as is usually the case in this genus. The 

 position of each of these pores is indicated by a single large 

 penial seta, which projects from the body-wall in a very con- 

 spicuous manner. These penial setse (fig. 1) measure 5 mm. 

 in length and 013 mm. in thickness. They are entirely 

 smooth, without ornamentation of any kind, and diminish 

 rather suddenly at the tip, which is very slightly hooked. 



The male pores lie on segment xviii., between the two 

 apertures of the spermiducal glands on either side. The 

 " seminal gutters/' which connect the three pores on either 

 side, are curved inwards towards the middle line, so as to 

 approach each other more closely in the middle than at the 

 ends. No genital papillae have been observed. 



The oviducal pores are quite easily seen on the ventral 

 surface of segment xiv. They are situated rather near the 

 middle line. 



The ordinary clnetas (fig. 2) arc very small for the sfze of 

 the worm. The minute size of the chaetse, however, is a 

 feature of almost universal occurrence in the genus. They 

 are, as usual, arranged in four pairs on each segment, 

 beginning with segment iii. They measure 0*8 mm. in 



* A specific diagnosis is given on \k [-">7. 



