40 
NOTES on the STRUCTURE of OIKOPLEURA. 
By W. A. Herpman, D.Sc., F.L.S., 
PROFESSOR OF NATURAL HISTORY IN UNIVERSITY COLLEGE, LIVERPOOL. 
With Plates I—IV. 
[Read 12th February, 1892.] 
For 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.8., 
of St. Annes-on-the-Sea, Lancashire, who has been 
successful in capturing several curious forms of Appen- 
diculariide, lately sent me for examination a very good 
specimen of an Otkopleura (probably O. flabellum, J. 
Mull.) which he had caught in his surface net from St. 
Anne’s pier in August, and had preserved in graduated 
alcohols from 30°/, 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 
