COE.— Nemerteans. 



PLATE 8. 



Carinomella lactea Coe. 



Fig. 57. Transverse section of body through posterior end of nephridial 

 region. Tlie two efferent ducts (nd) are almost exactly paired. 

 The dorsal infolding of integument is very marked, and all longi- 

 tudinal muscles are wanting in the median line above the probos- 

 cis sheath. The greatly thickened inner circular muscles almost 

 disappear a few sections farther posteriorly. The lateral nerve 

 cords are pressed closely against the outer circular muscles. 

 X 72. 



Fig. 58. Transverse section of body posterior to the nephridial region and the 

 thickening of inner circular muscles. These muscles are repre- 

 sented only by a few delicate fibers surrounding the proboscis 

 sheath and stomach. The muscular walls of the proboscis sheath 

 have almost disappeared, but the thick plate of longitudinal mus- 

 cles (Imp) lying between the sheath and the stomach has become 

 enormously developed. The lumen of the stomach has increased 

 suddenly in size, and the lateral nerve cords have migrated to the 

 midst of the longitudinal muscles, by which they are surrounded 

 on three sides, x 72. Cf. PI. 9, figs. 60, 61. 



Note.— Figs. 53, 54, 55, 56, 57, 58, 59, 63, Pis. 6 to 10 form a series of 

 transverse sections through the principal anatomical regions of the body. 



