1^02 Dr. F. E. BedJaid on 



in the two. In A the masses of muscles forming a hollow 

 sheath for the single penial seta were thicker and more 

 numerous than in the younger individual. In both, however, 

 they reached to the converging ends of the separate prostates, 

 and were thus more conspicuous than in the individual 

 figured by ]\[ichaelsen in the first of his two memoirs dealing 

 witli this genus. This, again, may be fairly ascribed to 

 greater maturity in specimen A. In these characters, 

 therefore, there are no generic differences from Michaelsen's 

 specimens. I have also identified the peculiar median body 

 thought at first by Michaelsen to be a median single ovary. 

 I have no suggestions to make as to the nature of this body, 

 except, perhaps, that it may correspond to the glandular 

 bodies attached to the end of the spermathecal sac in the 

 genus Eudriloides. 



One internal character, ho^-ever, fairly obviously cannot 

 be referred to differing maturity — that is, the conditions of 

 the intersegmental septa as to their relative thickness. 

 I have examined these in all of my examples, with particular 

 success in the case of specimen C, which was divided longi- 

 tudinally into two halves before further dissection. This 

 enabled an accurate picture of the septa to be seen. In his 

 earlier paper on Notykua emini, Michaelsen states that septa 

 5/6-9/10 are thick septa, but in the later paper that the 

 thickened septa are those lying between 5/6 and 11/12. Of 

 these, he adds, the middle ones are the most thickened. 

 There is an obvious discrepancy here. In his great work 

 upon the Oligochseta, in which the facts are presumably re- 

 vised, the thick septa are placed between 6/7 and 10/11, 5/6 

 and 11/12 being feebly thickened. In the example of 

 Notykus kilossensis, which I bisected longitudinally, the first 

 clearly marked septum lay just behind the gizzard, and thus 

 separated segments 5/6. Thereafter four septa, of which 

 the last two were thicker than those in front, separated seg- 

 ments 6/7-9/10. Septum 10/11 was a delicate septum 

 pushed forward by the mass of sperm collected in segment 1], 

 and might easily be missed owing to its lying for the most 

 part in contact with the septum in front. I shall again 

 refer to the septa in dealing with the spermathecal sac ; but, 

 in the meantime, I would point out that there would seem 

 to be a specific difference in the arrangement of these so far 

 back as segment 11. It may be also that the first example 

 of Notykus emini described by Michaelsen is different from 

 those subsequently examined, and is identical with my 

 species described here. 



The organs connected with reproduction, in addition to the 



