p. M. Turiihidl — Anatomy (otd Ilahits of Nereis vlrois. '269 



The inferior ligiihi of the u])per nuiius, with its two hjhes (tig. 12, 

 c, d) corresponds, apparently to the lobe (e) and its divisions, while 

 the lobe {k) of the upper ramus corresponds to the lobe (/) of the 

 lower ramus. In the upper ramus, the acicula and its partition do 

 not divide the bunch of setae, as it coAies out above the acicula. 

 The ventral cirrus arises from a slight protuberance of the inferior 

 side of the lower ramus (fig. 12, h). 



The feet are not all alike from one end of the body to the other ; 

 they change in form most along the anterior region, and in the first 

 five the variation is considerable ; along the middle and posterior 

 regions, it is slight in comparison, 



I have figured tlu' first five, the forty-fifth, and the one hundred-and- 

 ninth feet of a female worm, having one hundred and twenty-one 

 segments; also the first, fifth, forty-fifth, and one hundred-and-ninth in 

 a male worm of nearly equal size, but having one hundred and sixty- 

 one segments. These figures show the posterior view of the feet. 

 Those of the female will be first described, and then compared with 

 those of the male. 



In the first foot of the female (fig. 3) the upper ramus has only the 

 doi'sal cirrus and the superior ligula developed. The former is about 

 one-fifth longer and a little less than one-third as broad as the latter, 

 being very well dcA^eloped, wdiile the ligula is somewhat rudimentary. 

 The ligula is rounded and simple in shape, having a constriction at its 

 base. Of the lower ramus, all the parts are present. The posterior 

 setigerous lobe (/') is longer than the anterior setigerous lobe (e), and 

 is oval and flattened. The anterior setigerous lobe {e) is seen to be 

 divided by the acicula into two smaller terminal lobes (e and e'), in- 

 dicated by dotted lines where they are covered by the posterior seti- 

 gerous lobe (/"). The inferior ligula {g), of the lower ramus, is of 

 about the same size and shape as the superior ligula [h], and the infe- 

 rior cirrus (//), is like the superior cirrus {<(). The setse of the lower 

 ramus, as shown in the figure, extend just Ijeyond the posterior seti- 

 gerous lobe (/'). They are somewhat rudimentary and are for the 

 most part blunt. The acicula is also rather small. 



The second foot (fig. 4) has the anterior setigerous lobe (e), and the 

 acicula a little larger and better developed, and the dorsal cirrus is 

 seen to be a little shorter than that of the first foot; otherwise the 

 second foot is scarcely different from the first. 



In the third foot (fig. 5) the upper ramus has developed an inferior 

 ligula, setjB and acicula. It also has an anterior setigerous lobe 

 (c). This lobe is a part of the inferior ligula [d). It shows more 



