(40) 

 thati the other species. Tr.e least ix-ritatiou causes it to turn 

 up its hood ana to assume attitudes like those fii;urod by Master- 

 nm-i (15). In fact, judrin^ by the flcures and text of Master- 

 rr^an's pape^, it seems that there is considerable similarity be- 

 tween this larva and the one he has described. The two larvae 

 are very much alike in shape and bo tii have tlie late'-al stomach 

 diverticulae but t).e form that Maatennari describes has only t'.vo 

 masses o !^ blood co r^jus cles , The two species are not identical 

 nor is Actinotrocha Species, E. , identical 7,'i tii Actinotro ci-.a 

 branchiata from t l:e liorth Sea for, as Lonijchamps has pointed out 

 to -Tie, the latter has but two blood corpuscle masses, Lon-.cr. amps 

 has informed me that in Actinotrocha Species, E. , the adult ten- 

 tacles make their appearance in the same special v/ay that they 

 do in Actinotrocha branchiata (^ound near Helcpland aiid de- 

 scribed by J. Jlvlle c (19) ) and Masterman {16) says in liis pa- 

 per that the form he workea oa "does not appear to differ in any 

 essential re"spect" from Actinotrocha branchiata. There seems, 

 i;cv/ever, to be considerable difference in size between Actino- 

 trocha braiiChiata and Actinotro cna Species, E, , for, accorciin^^ 

 to Loncchajdips, the best developed specimen tiiat he obtained of 

 this species measured 2 mm while ti:e length o^ Actinotrocha Spe- 

 cies, B,, averages 1.^2 urn. 



Although Actinotro cha Species, A., seems to metamorphose 



