new Genus of Oligochceta. 89 



wall ; if the facts of this connoxion are of morphological 

 im))ortance, and not the result of a mere accident, they are 

 evidence that the oesophageal glands, like the " salivary 

 glands " (mucous glands of Acanthodrilas &c.) and the anal 

 glands 111 Acanthrodrilus multiporus, are partly at least formed 

 out of nejj/iridia. The glands appended to the alimentary 

 tract of Oligochaita would thus be for the greater part redu- 

 cible to a common origin. 



The nephridia of this species are enveloped in a very thick 

 layer of peritoneal cells ; there is no terminal vesicle at the 

 extremity of the nephridium ; the funnel opens as usual into 

 the segment in front. The first nephridium is in tiie fourth 

 segment ; they continue thence without any interruption to 

 the end of the body. The thick coating of peritoneal cells 

 is found in all the species of Gordiodrilus^ and gives to them 

 their whitish colour. The cells are in so many cases loaded 

 with spherical granules that not only the nucleus but some- 

 times the limiting membrane is concealed ; some of these 

 granules are, others are not, stained by the colouring reagent 

 used. The anterior nephridia have not this thick coating of 

 vesicular cells; the segment in which this investment is first 

 apparent seems to vary. In one individual the nephridia of 

 segment xiii. were the first to show an increased development 

 of the peritoneum ; in another I did not find these granular 

 cells before the nephridia of segment xix. 



The reproductive organs of this species are constructed 

 upon the same plan as in other species. The testes are two 

 pairs_, in segments x., xi.; the ovaries a single pair, in xiii. 

 There are no receptacula ovorum^ and the oviducts have the 

 usual relations. The sperm-sacs occupy segments ix.-xii. I 

 need say nothing about the vasa deferentia and atria. 



The spermatotheca3, on the other hand, are a little different 

 from those of other species. The form and minute structure 

 of one of these organs is illustrated in fig. 7, which repre- 

 sents a longitudinal section through the entire pouch, and is 

 naturally compiled from a number of sections. The pouch (there 

 are two pairs, in segments vii., viii.) consists of two parts, 

 firstly of a wide ctecal pouch, secondly of a narrow duct 

 connecting this with the exterior. At the junction of the two 

 is a pair of small diverticula, one on each side. One of these 

 two is longer than the other, though both are in point of size 

 rudimentary. The distal pouch is round or oval in form and 

 thin-walled ; it is lined by columnar epithelial cells and 

 covered externally by a thinnish layer of fibrous appearance 

 with interspersed imclei. la the diverticula the cells are 

 lower. There was no indication of the function which the 



