244 Dr. W. B. Benham on an 
is, at any rate, a very peculiar position for the “hearts ”’ to 
occupy. 
Perrier (loc. crt. p. 70) states that in the three somites 
immediately anterior to these intestinal hearts there exist as 
many pairs of “ véritables cceurs.” J believe that he is dealing 
really with dntestinal diver ticula, for he states that each of 
these organs is distinguishable into two very distinct parts :— 
(1) a superior, white, opaque, more voluminous region of 
ovoid form, and communicating at its narrow end with a 
vessel leading from the dorsal trunk ; and (2) a more ven- 
trally placed spherical region, with transparent walls, which is 
swollen with blood, and in relation to the ventral vessel. To 
quote his words:—‘Sur chacun d’eux on distingue deux 
parties bien distinctes: lune inférieure, & parois transparentes, 
gonflée par un sang bleuatre coagulé, de forme sphérique : 
Pautresupérieure, blanche , opaque, plus volumineuse, de forme 
ovoide, et s’abouchant par son petit bout avec le vaisseau qui 
conduit au trone dorsal.” 
And he speaks of the inferior region as an “ auricle” and 
the superior as ‘ ventricle ;”’ on the walls of the latter, he 
goes on to state, there can be seen some bluish veins starting 
from the apex, which soon disappear. 
He was led to the above conclusion owing to his having 
observed, as he thought, a similar “ heart”’ with ventricle 
and auricle in 7itanus (i. e. Geoscoler, Leuckart). 
Now I have examined a specimen of this worm, as I have 
previously mentioned*, and I find that the organ lying in 
somite x1ll1., whose relations were accurately described by 
Perrier, and which he mistook for a ‘ ventricle,” is in reality 
an intestinal diverticulum, having the same essential structure 
as the cesophageal g elands of Lumbricus f. 
I believe, then, “that the three pairs of organs are the 
characteristic intestinal diverticula which occur in this region 
in the other three species of Rh¢nodrilus. 
The genital organs (fig. 2).—There are two pairs of rather 
extensive sperm-sacs (sp.s.), which meet dorsally to a greater 
or less extent, and conceal the gizzard, the intestinal “diver- 
ticula, and other organs in this region of the body. The 
anterior sac on each side appears to extend through somites 
vill. to xi1., and the posterior through somites xiv. to Xvi. ; 
but more careful observation shows the former to arise in 
somite x1. and pass forwards into somite vi., and the posterior 
to extend through somites xii. to xvii. There are two pairs 
* “Studies on Earthworms, I.,” Quart. Journ. Mier. Sci. xxvi. p. 250. 
+ Mr. Beddard confirms my view of the matter in his paper in this 
Journal for February of the present year. 
