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MUSEUM OF COMPARATIVE ZOOLOGY. 20 
PLATE Ill. , 
Lepidonotus, Telepsavus, and Phyllochetopterus. 
a. Anus. @. C&sophagus. 
b.  Branchie. pl. Preoral lobe. 
e.  Elytron. s. Stomach. 
i. Intestine. t. Tentacle. 
m. Mouth. vg. Ventral gland. 
ms. Modified fourth segment. 
Side view of a young larva of Lepidonotus. 
Ventral view of a still more advanced larva of Lepidonotus. 
Older larva of the same. 
Oldest larva of Lepidonotus (dorsal view). 
o 5-15, Telepsavus (2). (Figs. 8-15 drawn by A. Agassiz.) 
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Youngest larva of Telepsavus (dorsal view). 
Older larva of Telepsavus (ventral view). 
Side view of the last. 
Tail of the last. 
Older larva of Telepsavus. 
Side view of the last. 
Side view of a still older larva. 
A larva still older (dorsal view). 
Oldest Telepsavus larva. 
Mouth and przoral lobe of the same. 
“14, 15. Differently formed spines of the oldest larva. 
“ 16-18. Larve of Phyllochctopterus (7). 
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Youngest larva of Phyllochctopterus. 
Side view of the same. 
Older larva of the same. 
“ 19, 20. Larve of Capitella. 
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PLATE IV. 
Wephthys and Lepidonotus. 
dc. Dorsal cirrus. m. Mouth. 
z. Intestine. ps. Pigment spots. 
j. Jaws. s. Stomach. 
k. Cephalic spots (ocelli 2). ve. Ventral cirrus. 
Youngest larva of Nephthys. 
Older larva of the same. 
The same. 
Still older larva from the ventral side. 
Later stage (ventral view). 
Lateral view of the last. : 
Larva with well-developed parapodia. 
Single parapodium of the same. 
