E. W. BERGEE ON THE CUBOMEDUS^E. 23 



giving information in the life of Charybdea, is evident from the 

 reaching motions of the proboscis after the removal of the sensory 

 clubs. Other centers of spontaneity in their order of importance 

 probably are : the radial ganglia (one experiment) ; the interradial 

 ganglia (?) ; the suspensoria, as shown by their supplying stimuli to 

 isolated pieces of the sides connected with them ; the frenula and the 

 velarium, the latter of which gave contractions when removed with 

 the frenula or in pieces only. No evidence is given that the frenula or 

 the velarium can impart their contractions to other tissue, though this 

 seems probable for the former. The proboscis can also contract of itself. 



Reflexes between the velarium, frenula, subumbrella, sensory clubs, 

 nerve, and any one pedalium, on the one hand, and the pedalia on 

 the other hand, are very common, and point to the pedalia with the 

 tentacles as organs of defense and offense. The pedalia serve also as 

 rudders in swimming. 



Finally, as judged by the results in this paper, Charybdea seems 

 to occupy, physiologically, a position intermediate between the 

 Hydromeclusas and the Scyphomedusa3. In its great activity as a 

 swimmer, in its response to light, and in its reflexes it is Hydrome- 

 dusan, while in the paralysis and recovery following the removal of 

 its marginal bodies, as also in its response with several pulsations 

 instead of one, when a deganglionated bell is stimulated, it is Scypho- 

 medusan. 



The observations on the Discomedusa?, Aurelia, Polyclonia, Cassi- 

 opoea, demonstrate the existence of motor nerve centers in the 

 marginal bodies; but that other centers are present is shown by the 

 recovery of pulsation following the removal of the marginal bodies 

 or the margin. These results are mainly confirmatory of those of 

 Romanes and Eimer. They differ from these in the fact that margins 

 of Polyclonia and Cassiopoea, with only one ganglion attached, 

 originated contractions distant from the ganglion. Removing of a 

 single lithocyst resulted in a slowing of pulsation, as did also the 

 removal of the oral lobes, though the immediate effect in the latter 

 case was an acceleration. Isolated pieces of the subumbrella could 

 contract. 



DR. CONANT'S NOTES. 



Below follow Dr. Conant's notes. They are printed about as 

 Conant left them. Their order of succession, however, has been 



