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I found this nervous system in all the typical Ophiurid larvæ 
which occurred during the time of my visit to the station, viz. 
besides the two figured, the larvæ of Ophiura albida , Amphiura 
fil i for mis, Ophiothrix fragilis and the Ophiopluteus compressns. 
a.l. antero-lateral arms; n. nervous band; oe. oesophagus; p.d. postero-dorsal arms; 
p.l. postero-lateral arms; p.o. postoral arms; r. rectum ; st. stomach ; 
v.l. vibratile lobe. 
Further I have found it in a great number of different Ophiurid 
larvæ in a preserved State, more or less distinctly. I have then 
no doubt that this is a structure found in all typical 
Ophiurid larvæ. 
It is a very remarkable faet that, while a special larval nerv¬ 
ous system is thus developed in both Holothurioid, Echinoid and 
