CYDONIUM MULLERI. 



Fig. 24. 



terized by having no solid axis developed in the interior of the com- 

 mon body. The Cydonium Mulleri (fig. 24) will give the reader a good 

 idea of the general appearance of one of these compound animals. 

 The central mass, or polypary, is entirely soft, being of a gelatinous, or, 

 rather, subcartilaginous texture. Upon cutting into it, it is found to be 

 intersected by tough fibrous bands, and not unfrequently contains calca- 

 reous spicula dispersed through its substance: no muscular fibre or 

 nervous matter has ever been detected in its composition, and its interior 

 is permeated by numerous wide canals variously disposed. 



(122.) Few objects exhibit to the 

 naturalist a more beautiful spectacle 

 than the compound animals of which 

 we are speaking. When found upon 

 the shore contracted and deformed, it 

 would be diflicult to imagine that they 

 were really organized beings, much less 

 possessed of any elaborate conforma- 

 tion ; yet on placing one of them in a 

 tumbler of sea -water and watching it 

 attentively, its true nature is gradually 

 revealed: the central mass expands 

 in all directions, exhibiting the cells 

 upon its surface, from which in time 

 the countless flower-like polyp* are 

 protruded, which, stretching out their 

 arms in all directions, wait for the 

 approach of prey. A scene like this 

 naturally leads us to inquire concern- 

 ing some points of physiology connected with their economy; and 

 several questions obtrude themselves upon us, which, as they are appli- 

 cable to the whole group of compound polyps, may be well discussed 

 in this place. 



(123.) That there is a community of nutrition or, in other words, 

 that food taken and digested by the individual polyps is appropriated to 

 the support of the general body is generally admitted ; but is there a 

 community of sensation, so as to render the entire mass one animal, 

 capable of consentaneous movements ? or is each polyp independent of 

 the rest in its sensations and actions ? Upon this there are different 

 opinions, some regarding the whole as a single animal, each part being 

 in communication with the rest, and thus participating in the feelings 

 and movements of the others, whilst some consider every polyp as a 

 distinct creature, independent of the rest. The solution of this problem 

 is a matter of some difficulty ; but there are several facts which may in 

 some measure enlighten us upon the subject. From the absolute want 

 of nervous filaments which might bring into communication distant 



Cydonium Mulleri. 



