SECOND REPORT on the NUDIBRANCHIATA of the 
heavtb GC. DES ERICL, 
By W. A. Herpman, D.Sc., F.LS., F.R.S.E., 
PROFESSOR OF NATURAL HISTORY; AND 
J. A CEGRB, 
ASSISTANT IN THE NATURAL HISTORY DEPARTMENT, UNIVERSITY COLLEGE, LIVERPOOL. 
With Plate XII. 
[ Read 10th May, 1889.] 
In Professor Herdman’s Report upon the Nudibranchiata, 
in the first volume of the ‘“‘Fauna,” published in 1886, 
forty-two species were referred to as having been found in 
this district. We have now, as the result of the last three 
years’ exploration of the neighbourhood, and especially 
as a consequence of the establishment of the Biological 
Station on Puffin Island, to place on record some additional 
localities for many of these species, including some of the 
rarer ones, some information in regard to their relative 
abundance and times of spawning, and we have to add to 
the list Fiona marina, a rare species new to the district. 
We also include in this report some anatomical and 
histological observations upon a few of the species of 
the neighbourhood, especially upon the hepatic ceca of 
Dendronotus and the apertures in the cerata of Holis ; and 
we append a short note upon some British specimens of 
Hero formosa, Loven, a Scandinavian Nudibranch. 
The greater part of the practical work for this report 
has been carried out by Mr. Clubb, in the zoological 
laboratory of University College; while Prof. Herdman 
has suggested the lines of investigation, has examined all 
the specimens and sections, and has discussed the results. 
