Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Mayer. — Staurocephalus gregaricus. 
18. 
19. 
20. 
21. 
22. 
23. 
24. 
25. 
26. 
27. 
PLATE 3. 
Larva of Staurocephalus gregaricus, nov. sp., 10 days old. 
Dorsal view of a young worm 16 daysold. The animal now ceases to 
swim through the water, but will readily burrow beneath the surface 
of sand upon the bottom of the aquarium. Length 0.8 mm. 
Ventral view of the head end of a young worm 16 days old, showing the 
“jaws” of the esophagus. 
Dorsal view of a worm 26 days old. Length 1.2 mm. 
Side view of a worm 26 days old, showing the “‘ jaws ” in the csophagus. 
(m) mouth. 
Side view of the posterior segment of a worm 26 days old, showing cirri. 
Dorsal view of a worm 34 days old, showing the beginnings of the mature 
coloration immediately back of the eyes. Length 1.5 mm. 
Seta from a worm 26 days old. 
Dorsal view of the dorsal “jaws” from the esophagus of a worm 26 
days old. 
Side view of the dorsal “ jaws ” from the esophagus of a worm 26 days 
old. 
