EXPERIMENTAL OBSEEVATIONS ON PENNATULIDS. 443 
Experimental Observations on the Organs of 
Circulation and the Powers of Locomotion 
in Pennatulids. 
By 
Editli M. Miisgrave, D.Sc. (nee Pratt), 
Late Honorary Research Fellow in the University of Manchester. 
With Plates 26 and 27. 
The study of Pennatulids has long engaged the atten- 
tion of zoological workers. In the publications of the eigh- 
teenth century wonderful and fantastic accounts are given of 
the habits, form and movements of members of this interesting 
family ; of their graceful flight through the water, their 
exceeding luminosity by night, and their gymnastic contor- 
tions even in captivity. In those early days of zoological 
research a “ sea pen ” was regarded as a single individual 
provided with lateral “ fins ” for swimming purposes, and 
a mouth opening at the base, Avhich served also for the excre- 
tion of waste matters. 
Later accounts on the subject are written in a more tem- 
perate spirit, and in them we observe a general contradiction 
of the apparently extravagant statements of early writers. 
In the tenth edition of the ‘ Systema Naturm ’ of Linnaeus 
(1758) a diagnosis of Pennatula phosphorea is gdven, in 
which mention is made of a basal opening to the exterior (os 
baseos commune rotundum). Six years later Ellis (1764, 
pp. 419-428) published an excellent account of an investigation 
of this species, in which he denies the existence of the mouth 
or basal opening. Of the habits of this interesting species he 
says : 
VOL. 54, PART 3. — NEW SERIES. 
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