136 



the more highly developed structures, the nerve-corpuscles, 

 are those which regulate and primarily carry on the 

 action. 



It may further be allowable to suggest that, although in 

 the nervous actions connected with sensibility and movement 

 throughout the body, the travelling of impressions plays a 

 most important part, yet it seems more probable that in the 

 cerebral hemispheres such travelling has only the subsidiary 

 end to serve of bringing all the corpuscles into communi- 

 cation, and that it is a condition of these, in. some degree 

 comparable with the contracted condition of a muscle, which 

 is the physical element necessary for mental action ; that the 

 total amount of mental action at one time is thus dependent 

 on the total amount of the physical action ; and that it is very 

 questionable if there be any closer connection between the 

 special qualities of the mind and the structure of the 

 brain . 



On the Embryonic Form of Nematobothrium filarina. 

 Van Ben. By Dr. Edouard Van Beneden. Plate VIII. 



In his memoir on the Intestinal Worms, M. P. J. Van 

 Beneden made known an extremely remarkable animal Avhich 

 he described under the name of Nematohotlirium filarina} It 

 lives parasitically in Sciana aquila, a fish which is found 

 sometimes on our coasts and which is met with from time to 

 time in the Channel and on the coasts of the Atlantic. But 

 as it is always a relatively rare fish, one has not at all times 

 the opportunity of studying the singular parasites which this 

 animal harbours. 



Nematobothrium differs considerably from all known worms. 

 It has the external form of a Nematod, attains an enormous 

 length, often more than a metre, and is always rolled up on 

 itself, forming a regular ball, the volume of which varies 

 between that of a large nut and an ordinary orange. This 

 ball is lodged beneath the skin, which covers the region of 

 the shoulder-girdle of the fish, in a regular closed cyst, which 

 presents exteriorly the aspect of a voluminous tumour. 



The Nematobothrium is not free in its cyst ; it is lodged 

 in a membranous tube rolled up like the worm which it 

 lodges, which acquires adhesions on all sides, and from this 



' P. J. Van Beneden, 'Memoir sur les Vers Intcstinaux,' Paris, IS5S, 

 p. 107, pi. xiii. 



