PLATE 5 
EXPLANATION OF FIGURES 
Nectonemertes mirabilis 
14 Transverse section through head of mature male; slightly reconstructed 
from adjacent sections, showing brain lobes with dorsal (dc) and ventral (vc) 
commissures; stomach (sf), immediately beneath ventral commissure, and a 
single lobe (ied) of the anterior diverticulum of intestinal caecum. A fully mature 
spermary (sp) is shown, with seminal vesicle leading to ventral surface of head. 
x 24. i 
15 Portion of a transverse section of body, showing an immature spermary 
with developing seminal vesicle (sv) with its simple epithelial lining extending 
through body wall. The muscular wall (m) of the gonad encloses the developing 
spermatogonia (spg) and spermatocytes (spc); cm and lm, circular and longitudi- 
nal body musculatures, respectively; bm, basement layer. 
16 Portion of transverse section of body, showing tangential section of a 
gonad with the musculature (m) cut longitudinally, and the seminal vesicle cut 
transversely. Lettering as in figure 15. X 300. 
17 Sagittal median section of anterior portion of body. Slghtly recon- 
structed from adjacent sections, showing opening of the rhynchodeum (ro), 
attachment of proboscis sheath (ps), mouth (mo) with its folds of epithelium, 
leading through a short cesophagus to stomach (st), and the latter to pylorus 
(pyl); ic, intestinal caecum; icd, diverticula of same; in, intestine; 7d, intestinal 
diverticula; de, dorsal brain commissure, the ventral commissure being also shown 
above stomach. X 24. 
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