80 DESCRTPTIONS OF EA.RTHWORMS. 



posterior end of the body, aud the bristles of each pair 

 are placed close to each other. Though this difference 

 between my description and that of Perrier may perhaps do 

 arise some doubt about the identity of our specimen with 

 A. gigas , I believe our observations agree with one another 

 in so many points to give sufficient grounds for my assertion. 



The nephridiopores are very large and apparent in the 

 segments of the clitellum and the posterior region of the 

 body; they are situated in front of the external dorsal setae , 

 the first of them in the intersegmental groove of segment 

 3 and 4. Dorsal pores are absent. Like Perrier I have 

 not been able to find the orifices of the genital organs. 



On opening the worm (fig. 1) we are struck by the 

 immense development of the anterior septa; the 5th to 10th 

 septum are very thick , overlapping one another and bid- 

 ding totally the intestine and other organs. In the two 

 anterior septa the central portion is carried far backward 

 and has another structure and colour than its peripheri- 

 cal portion; it is of a pale brown colour and appears 

 to be covered with a layer of short prismatical bodies of 

 a fine granular structure, standing vertically on the sur- 

 face of the septum. In the following septa the central 

 modification spreads out peripherically and reaches the 

 periphery in the ninth septum , giving to it the singular 

 appearance over its whole surface. The tenth septum is 

 not so thick as those in front of it. All these septa are 

 fixed to each other by meaus of longitudinal muscle- 

 strands. The segments 11, 12 and 13 are covered at their 

 internal side with a brown , horney layer, thicker than the 

 longitudinal muscular layer and showing the same structure 

 as the modified septa. As suggested by Perrier this orga- 

 nisation most give firmness as well as strength to the 

 anterior region of the body for the purpose of burrowing. 



The intestinal canal (fig. 2) commences with a 

 large pharynx, the wall of which shows no glandular 

 structures as in many other Lumbricidae ; then follows the 

 oesophagus , with a rather wide lumen , which , before passing 



iN'otes from the Leyden JVIuseuin , Vol. ^III. 



