374 KARM NARAYAN BAHL 
which are also pulsatile but supply blood to some of the organs 
directly, e.g. the gizzard and the pharyngeal nephridia. I have 
adopted Bourne’s suggestion (1, p. 64 n.) of naming all rhythmi- 
cally contractile, circularly disposed vessels as ‘hearts’, which 
term thus includes even the anterior branches of the dorsal 
vessel which do not join the ventral vessel. 
TEXT-FIG. 6, 
rv. + 
lab.oesv. ue 
V.V. 
.c 
15 
A diagrammatic transverse section of the earthworm through the 
region of the ‘ latero-intestinal ’ hearts. In the right half is shown 
the intersegmental septum just behind the ‘heart’. d.v.= 
dorsal vessel; /t.=latero-intestinal heart ; 7.s.=intersegmental 
septum ; ¢nt.v.=integumentary vessels taking blood (venous) to 
the lateral oesophageals and the supra-intestinals ; lat.oes.v.= 
latero-oesophageal vessels ; 7.v.=a ring-vessel in the oesophagus ; 
$u.i.v,=supra-intestinal vessel ; v.v.= ventral vessel. 
Again, Bourne (1, p. 64n.), following Perrier, distinguishes 
‘lateral hearts ’ from the ‘ intestinal hearts ’ according as they 
are connected dorsally with the dorsal or supra-intestinal 
vessels. ‘The ‘hearts’ in the twelfth and thirteenth segments 
in Pheretima communicate dorsally with both the dorsal 
and supra-intestinal vessels and are therefore ‘ latero-intestinal ’ 
hearts, while the ‘ hearts’ in the seventh and ninth segments 
belong to the category of ‘lateral hearts’. Coming to the 
‘loops ’ of the tenth and eleventh segments, we find that they 
