The visceral ganglion of Pecten, with some 
notes on the physiology of the nervous system, and 
an inquiry into the Innervation of the Osphradium in 
the Lamellibranchiata. 
W. J. Dakin. M. Se, 
Demonstrator and Assistant Lecturer in Zoology. University of Belfast, Ireland. 
With 1 text-figure and plates 1,2. 
Introduction. 
I feel that some explanation is necessary for the length of the title 
of this paper, and the combination of the subjects treated. The Stimulus 
to the research came from some observations made on the visceral gang- 
lion of Pecten whilst at work on a memoir on that animai (1909). It 
became evident that the structure of this nerve centro was far more com- 
plicated than is usuai in the lamelbbranchiata, in fact it was unique, 
but a detailed treatment was beyond the scope of the memoir. I deter- 
mined therefore to make a more extensive research into the structure 
of this ganglion, and to work out the course of the nerves entering it. 
As a result a little attention was given to the question of the Innervation 
of the osphradium, using several other species of lamellibranchs for 
comparison. 
As a naturai sequence to the histological study of the ganglion of 
Federi, some experiments were made for the purpose of determining the 
function of certain senso organs and the nature of the nerves. 
The first section of this research was completed at Naples, and the 
remainder at the Port Erin Biological Station, England. I should like 
to express my thanks here to the British Association for the privilege 
of occupying their table at the Zoological Station of Naples and to the 
staff of that Institution for their many kindnesses, also to Prof. Herdman 
for his kind help at Port Erin. 
Mittheilungen a. d. Zoo!. Station zu Neapel. Bd. 20,1. X 
