31 



[From Trans. Biol. Soc, L'pool. Vol. VI.] 



NOTES on the STEUCTUEE of OIKOPLEUEA. 

 By W. a. Herdman, D.Sc, F.L.S., 



PROFESSOR OF KATUllAL HISTORY IN UNIYERSITY COLLEGE, LIVERPOOL. 



With Plates I— IV. 



[Read 12tli February, 1892.] 



Foe several years, as opportunity offered, I have been 

 making occasional observations on the structure of Appen- 

 dicularians, living and preserved, from Puffin Island and 

 other parts of Liverpool Bay. Mr. G. Swainson, F.L.S. , 

 of St. Annes-on-the-Sea, Lancashire, who has been 

 successful in capturing several curious forms of Appen- 

 diculariidge, lately sent me for examination a very good 

 specimen of an OiJcoj^Ieura (probably 0. flahellum, J. 

 Miill.) which he had caught in his surface net from St. 

 Anne's pier in August, and had preserved in graduated 

 alcohols from 307o to absolute, and which had been im- 

 bedded in paraffine, stained with Babes' safranin solution 

 and sectionised by Dr. E. C. Bousfield with the Caldwell 

 automatic microtome. My thanks are due to Mr. Swainson 

 and Dr. Bousfield for their kindness in enabling me to ex- 

 amine this form. As their specimen seems to have been 

 in excellent condition, and shows some interesting points 

 rather well, I have made it the basis of the following 

 observations (in which the substance of my former notes 

 is incorporated) and have drawn in the accompanying 

 plates the more important of the sections, enough of them, 

 I think, to form a guide to the complete structure of the 

 animal. I have also given in figure 9 on plate IV. a 

 lateral view of the animal, reconstructed from the serial 

 sections, which may be useful in interpreting the individual 



