vou2.pt. 2.] A TAXOXOMIC STUDY OF THE SALPIDAE METCALF. 17 



It is necessary to refer briefly to the embryonic development of this 

 eye. Early in its development the central nervous system of the 













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Fig. 4.— Ctclosalpa pinnata, solitary form, a transverse section of the 

 ganglion and the eye. x 150 diameters. from metcalf (1893, c). 



m ryo is a short hollow tube opening in front through a funnel. 

 Later the walls of the posterior portion of the tube thicken, first 



Iw. 



cle P- d.l/' V 



Fig. 5.— Cyclosalpa pinnata, embryo, a sagittal section of the de- 

 veloping GANGLION AND CILIATED FUNNEL. X 180 DIAMETERS. FROM 

 METCALF (1S93, C). 



ventral ly, then dorsally (fig. 5), to form the ganglion, the lumenTof 

 the tube becoming obliterated. At the same time the anterior por- 



