44.6 E. A. ANDREWS. 
It may in some cases branch out one third of the way towards 
the head from the tail, and is then usually at right angles to 
the body proper. This branch may be so small as to be a 
mere bud, or it may attain a considerable length. I think 
that both sides are supplied with intestine and nerve-cord.” 
To his courtesy I am indebted for three of these specimens, 
as well as for five others obtained the past summer, 1893, at 
the same place. 
For convenience these eight cases of bifurcation of the body 
posterior to the head region may be referred to as the specimens 
A, Bs Cy VG Weeks YG aa: 
The first, A, was in alcohol, having been carefully hardened 
for examination by means of sections. The other two, B and 
C, were stained and mounted in Canada balsam. 
The general flat, broad shape and colour of this Annelid are 
indicated in fig. 16, which, however, is not as dark as the 
animal usually appears. 
In the specimen A the body is bifurcated in such a manner 
that there are two equal terminals, one dorsal and one ventral, 
as seen in the side view (fig. 11). At the same time each 
terminal may be regarded as a right or a left branch, since 
their tips diverge widely from side to side as well as up and 
down, and since, moreover, the terminals and trunk come 
together obliquely, that is, the dorsal terminal is somewhat 
twisted towards the right, the ventral one slightly towards the 
left, or as we may express it, the median planes of the three 
parts diverge and are twisted so that they have no line in 
common, only a point. 
The parapodia continue along the ventral or right terminal 
with little interruption in their line of sequence, but the para- 
podia of the dorsal terminal are separated from those of the 
trunk by a wide interval, and do not have the same direction as 
those of the trunk. In fact, the dorsal terminal looks like a 
dorsal interpolation grafted upon the trunk where it bends 
down, and somewhat to the right, as the ventral terminal. 
In this specimen the number of setigerous somites in the 
trunk or region anterior to the bifurcation is 27, while in each 
