308 MR. n. H, STIRRUP ON 



of a number of small, rounded, highly refractive bodies. From 

 their appearance one would almost think they were ocelli of some 

 kind. However, their function is, I believe, unknown, and more 

 work is required upon them before they could definitely be called 

 ocelli. 



In E. pellucidus there is nothing in the nature of winged 

 expansions to the nerve-cord, which have been described in some 

 Enchytraeids (6). The so-called "copulation-glands," which is 

 the name given to masses of large cells which almost surround 

 the nerve-cord in segments 13 and 14 (14), are not present in 

 Enchytrceus pellucidus. 



The ventral nerve-cord sends out numerous branches to the 

 body- wall. Fig. 12 (PI. XL VII.) shows a longitudinal section of 

 the body-wall passing through the nerve-cord. Here the nerve- 

 branches are very thick strands and can be seen passing through 

 the longitudinal muscles to the epidermis. 



The nuclei of the nerve-cord are always situated in the ventral 

 region only; the rest of the nerve-cord is fibrous in structure 

 and has no nuclei. 



In transverse sections, one almost invariably sees a number of 

 clear spaces, usually two or three, in the nerve-cord. These have 

 every appearance of being giant fibres running longitudinally 

 along the cord. 



It would be as well to describe here some curious bodies in the 

 nerve-cord, which I have only seen twice in the large number of 

 Enchytraeids I have examined. I saw them first in a small 

 immature Enchytraeid in each of segments 8, 9, and 12. Just 

 recently I have again seen an exactly similar body in a fully 

 mature specimen of E. pellucidus; in this case it appeared in 

 segment 14. Under the high power they appeared to be very 

 granular, definite, oval bodies, quite distinct from the nerve-cord 

 itself, but embedded in it (PI. XLYII. fig. 11 a, h). I have seen 

 no description of these bodies elsewhere, and am inclined to think 

 that they were of a parasitic nature, but since I have only seen 

 them twice, I have been unable to do more than describe them. 



Gcelomic Corpuscles. — The coelomic corpuscles in E. pellucidus 

 are comparatively few in number. In some Enchytrseids they are 

 so numerous that it is very difficult to examine the various 

 organs in the living worm ; but E. pellucidus is so transparent 

 that the nephridia, brain, etc., can be seen quite easily. 



My observations on the coelomic corpuscles agree very closely 

 with those of Goodrich in his description of E. ho7-tensis (7). 



(a) By far the commonest and largest type of corpuscle is oval 

 in shape and flattened (text-fig. 63 A). It varies from 47 ^ to 

 23^ in length and from 12^ to 8^ in breadth. It is very 

 granular, with a clearer spot in the centre, the nvicleus. It is 

 usually rounded at one end and at the other end drawn out 

 into one or two threads, the points of attachment to the coelomic 

 epithelium. Whilst examining the living worm, one can always 

 see a number of these corpuscles attached to the walls of the 



