extending from tbe 2(iili l:o the 31st .segment. The modi- 

 fication of the integument, however, is only ventral; it does not die 

 a, way gradually, and there is a sharp demarcation from the dorsal 

 surface which is unmodified. The boundaries of the segments 

 could be noticed with perfect ease in this region. The seta?, how- 

 ever, were not obvious. 



Another external feature ot' some little importance, which was 

 observed, is the presence of papilte. They are situated ventrally, 

 bat are not perfectly symmetrical in their arrangement, inasmuch 

 as they correspond to setse which are themselves in this species 

 scattered after the fashion of Pontoscolex and some other Greosco- 

 lecids. Of these papillae there are 4 on each of segments xi., xii., 

 xxiii., xxiv., and 2 on each of segments xxxi., xxxii. They, are oval 

 in form, the long axis coinciding with the transverse diameter of 

 the body ; the middle of each is higher than the periphery. 



These papillae were naturally plainer upon the mature than upon 

 the immature exam[)les. The sette which lie in the middle of tlie 

 areas formed by these papillse are larger than those elsewhere, but 

 do not appear to present any marked difference of form. We 

 should add that the spiny tip of the seta?, on account of which the 

 generic name was first bestowed, is not always perfectly obvious ; 

 but this may be very likely due to wear and tear. 



As to internal characters, the main addition that we have to make 

 to the original description concerns the sperm-sac. In the original 

 non-mature example these, though long, only occupied 15 or 

 20 segments. In an immature example from the material now 

 before us the sperm-sac passed back to as far as the 90th segment ; 

 in a mature example much farther, to the 119th. They thus 

 occupy in the latter case no less than 109 segments. Their 

 structure is thus : in segment xi. the sac commences with a dilated 

 pouch, ilattish, bigger ventrally than dorsally ; in the next segment 

 they are thinned down to a fine thread-like tube attached to the 

 lateral walls of the intestine. About segment xxxiii. the sac 

 dilates into a string of irregular-shaped sacs arranged without any 

 regard to segmentation. Somewhere about segment Ixxv. these 

 irregular sacs bear numerous processes, as was figured in the paper 

 in the ' Quarterly Journal of Microscopical Science ' already 

 referred to. 



There are six thickened septa lying behind the gizzard (which 

 is in segment vi.). jS'o calciferous glands were seen. 



We should add that the mature worm is larger than the originally 

 described immature example. One of ours measured 113 mm. by 

 5 mm. in diameter. 



